Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each...

LQ

Lê Quỳnh Anh

11 tháng 6 2018

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the question. Mountaineers have noted that as they climb, for example, up to the 12,633–foot Humphreys Peak in the San Francisco Peaks in Arizona, plant life changes radically. Starting among the cacti of the Sonoran Desert, one climbs into a pine forest at 7,000 feet and a treeless alpine tundra at the summit. It may seem that plants at a given altitude are associated in...

Đọc tiếp

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the question.

Mountaineers have noted that as they climb, for example, up to the 12,633–foot Humphreys Peak in the San Francisco Peaks in Arizona, plant life changes radically. Starting among the cacti of the Sonoran Desert, one climbs into a pine forest at 7,000 feet and a treeless alpine tundra at the summit. It may seem that plants at a given altitude are associated in what can be called “communities” – groupings of interacting species. The idea is that over time, plants that require particular climate and soil conditions come to live in the same places, and hence are frequently to be found together. Scientists who study the history of plant life are known as paleobotanists, or paleobots for short. They build up a picture of how groups of plants have responded to climate changes and how ecosystems develop. But are these associations, which are real in the present, permanent?

A great natural experiment took place on this planet between 25,000 and 10,000 years ago, when small changes in the earth’s orbit and axis of rotation caused great sheets of ice to spread from the poles. These glaciers covered much of North America and Europe to depths of up to two miles, and then, as the climate warmed, they retreated. During this retreat, they left behind newly uncovered land for living things to colonize, and as those living things moved in they laid down a record we can read now. As the ice retreated and plants started to grow near a lake, they would release pollen. Some would fall into the lake, sink to the bottom, and be incorporated into the sediment. By drilling into the lake bottom it is possible to read the record of successive plant life around the lake. The fossil record seems clear; there is little or no evidence that entire groups of plants moved north together. Things that lived together in the past don’t live together now, and things that live together now didn’t live together in the past. Each individual organism moved at its own pace. The fossil record seems to be telling us that we should be thinking about preserving species by giving them room to maneuver – to respond to environmental changes.

Which of the following can be inferred from the passage?

A. That the migratory patterns of plants are dependent upon changes in climate

B. That current associations of plants are similar to those in the past

C. That modern conservation methods should consider the migratory patterns of plants

D. That another ice age is likely to occur at some time

#Mẫu giáo

1

DH

Dương Hoàn Anh

11 tháng 6 2018

Kiến thức: Đọc hiểu

Giải thích:

Điều gì có thể được suy ra từ đoạn văn?

A. Các kiểu di cư của thực vật phụ thuộc vào sự thay đổi của khí hậu.

B. Các quần thể thực vật hiện nay tương tự như trong quá khứ.

C. Phương pháp bảo tồn hiện đại nên xem xét các mô hình di cư của thực vật.

D. Một kỷ băng hà khác có khả năng xảy ra vào một lúc nào đó.

Thông tin: Each individual organism moved at its own pace. The fossil record seems to be telling us that we should be thinking about preserving species by giving them room to maneuver – to respond to environmental changes.

Tạm dịch: Mỗi sinh vật riêng lẻ di chuyển theo tốc độ riêng của nó. Mẫu hóa thạch dường như đang nói với chúng ta rằng chúng ta nên suy nghĩ về việc bảo tồn các loài bằng cách cho chúng cơ hội để vận động – để thích ứng với những thay đổi môi trường.

Chọn C

Dịch bài đọc:

Những người leo núi đã chú ý rằng khi họ leo núi, ví dụ, lên đến đỉnh Humphreys cao 12,633 feet ở Đỉnh San Francisco ở Arizona, đời sống thực vật thay đổi hoàn toàn. Bắt đầu giữa những cây xương rồng của sa mạc Sonoran, một người leo lên một khu rừng thông ở độ cao 7,000 feet và một lãnh nguyên núi cao vô tận ở đỉnh núi. Dường như các loài thực vật ở độ cao nhất định có liên quan đến những gì có thể được gọi là “quần xã” – nhóm các loài tương tác. Ý tưởng là theo thời gian, các loài thực vật đòi hỏi điều kiện khí hậu và đất đai đặc biệt đến sống ở cùng một nơi, và do đó thường được tìm thấy cùng nhau. Các nhà khoa học nghiên cứu về lịch sử của đời sống thực vật được gọi là các nhà cổ sinh vật học (paleobotanists), hay viết tắt là “paleobots”. Họ phác họa nên một bức tranh về cách các nhóm thực vật đã ứng phó với biến đổi khí hậu và cách các hệ sinh thái phát triển. Nhưng những mối quan hệ đang xảy ra trên thực tế này có kéo dài mãi mãi?

Một thí nghiệm tự nhiên tuyệt vời đã diễn ra trên hành tinh này từ giữa 25,000 đến 10,000 năm trước, khi những thay đổi nhỏ trong quỹ đạo và trục quay của Trái đất khiến những tảng băng lớn lan ra từ các cực. Những dòng sông băng bao phủ phần lớn Bắc Mỹ và châu Âu tới độ sâu lên đến hai dặm, và sau đó, khi khí hậu ấm lên, chúng tan ra. Trong suốt quá trình tan chảy, chúng đã bỏ lại vùng đất mới chưa được khám phá để sinh vật sống, và khi những sinh vật đó chuyển đến chúng đã lập một kỷ lục chúng ta có thể đọc ngay bây giờ. Khi băng tan và thực vật bắt đầu mọc gần hồ, chúng sẽ tỏa ra phấn hoa. Một số sẽ rơi xuống hồ, chìm xuống đáy và tạo thành trầm tích. Bằng cách khoan vào đáy hồ, người ta có thể đọc được sự phát triển của đời sống thực vật kế tiếp quanh hồ. Mẫu hóa thạch có vẻ rõ ràng; có rất ít hoặc không có bằng chứng cho thấy toàn bộ các nhóm thực vật di chuyển về phía bắc cùng nhau. Những thứ sống cùng nhau trong quá khứ hiện đang không sống cùng nhau và những thứ sống cùng nhau bây giờ đã không sống cùng nhau trong quá khứ. Mỗi sinh vật riêng lẻ di chuyển theo tốc độ riêng của nó. Mẫu hóa thạch dường như đang nói với chúng ta rằng chúng ta nên suy nghĩ về việc bảo tồn các loài bằng cách cho chúng cơ hội để vận động – để thích ứng với những thay đổi môi trường.

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LQ

Lê Quỳnh Anh

24 tháng 11 2019

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the question. Mountaineers have noted that as they climb, for example, up to the 12,633–foot Humphreys Peak in the San Francisco Peaks in Arizona, plant life changes radically. Starting among the cacti of the Sonoran Desert, one climbs into a pine forest at 7,000 feet and a treeless alpine tundra at the summit. It may seem that plants at a given altitude are associated in...

Đọc tiếp

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the question.

Mountaineers have noted that as they climb, for example, up to the 12,633–foot Humphreys Peak in the San Francisco Peaks in Arizona, plant life changes radically. Starting among the cacti of the Sonoran Desert, one climbs into a pine forest at 7,000 feet and a treeless alpine tundra at the summit. It may seem that plants at a given altitude are associated in what can be called “communities” – groupings of interacting species. The idea is that over time, plants that require particular climate and soil conditions come to live in the same places, and hence are frequently to be found together. Scientists who study the history of plant life are known as paleobotanists, or paleobots for short. They build up a picture of how groups of plants have responded to climate changes and how ecosystems develop. But are these associations, which are real in the present, permanent?

A great natural experiment took place on this planet between 25,000 and 10,000 years ago, when small changes in the earth’s orbit and axis of rotation caused great sheets of ice to spread from the poles. These glaciers covered much of North America and Europe to depths of up to two miles, and then, as the climate warmed, they retreated. During this retreat, they left behind newly uncovered land for living things to colonize, and as those living things moved in they laid down a record we can read now. As the ice retreated and plants started to grow near a lake, they would release pollen. Some would fall into the lake, sink to the bottom, and be incorporated into the sediment. By drilling into the lake bottom it is possible to read the record of successive plant life around the lake. The fossil record seems clear; there is little or no evidence that entire groups of plants moved north together. Things that lived together in the past don’t live together now, and things that live together now didn’t live together in the past. Each individual organism moved at its own pace. The fossil record seems to be telling us that we should be thinking about preserving species by giving them room to maneuver – to respond to environmental changes.

The word “radically” in paragraph 1 is closest in meaning to _______.

A. quickly

B. variably

C. dramatically

D. demonstrably

#Mẫu giáo

1

DH

Dương Hoàn Anh

24 tháng 11 2019

Kiến thức: Đọc hiểu, từ vựng

Giải thích:

radically (adv): triệt để, hoàn toàn

quickly (adv): nhanh variably (adv): thay đổi

dramatically (adv): đột ngột và ở mức độ rất lớn demonstrably (adv): rõ ràng, minh bạch

Thông tin: Mountaineers have noted that as they climb, for example, up to the 12,633–foot Humphreys Peak in the San Francisco Peaks in Arizona, plant life changes radically.

Tạm dịch: Những người leo núi đã chú ý rằng khi họ leo núi, ví dụ, lên đến đỉnh Humphreys cao 12,633 feet ở Đỉnh San Francisco ở Arizona, đời sống thực vật thay đổi hoàn toàn.

Chọn C

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LQ

Lê Quỳnh Anh

17 tháng 5 2019

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the question. Mountaineers have noted that as they climb, for example, up to the 12,633–foot Humphreys Peak in the San Francisco Peaks in Arizona, plant life changes radically. Starting among the cacti of the Sonoran Desert, one climbs into a pine forest at 7,000 feet and a treeless alpine tundra at the summit. It may seem that plants at a given altitude are associated in...

Đọc tiếp

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the question.

Mountaineers have noted that as they climb, for example, up to the 12,633–foot Humphreys Peak in the San Francisco Peaks in Arizona, plant life changes radically. Starting among the cacti of the Sonoran Desert, one climbs into a pine forest at 7,000 feet and a treeless alpine tundra at the summit. It may seem that plants at a given altitude are associated in what can be called “communities” – groupings of interacting species. The idea is that over time, plants that require particular climate and soil conditions come to live in the same places, and hence are frequently to be found together. Scientists who study the history of plant life are known as paleobotanists, or paleobots for short. They build up a picture of how groups of plants have responded to climate changes and how ecosystems develop. But are these associations, which are real in the present, permanent?

A great natural experiment took place on this planet between 25,000 and 10,000 years ago, when small changes in the earth’s orbit and axis of rotation caused great sheets of ice to spread from the poles. These glaciers covered much of North America and Europe to depths of up to two miles, and then, as the climate warmed, they retreated. During this retreat, they left behind newly uncovered land for living things to colonize, and as those living things moved in they laid down a record we can read now. As the ice retreated and plants started to grow near a lake, they would release pollen. Some would fall into the lake, sink to the bottom, and be incorporated into the sediment. By drilling into the lake bottom it is possible to read the record of successive plant life around the lake. The fossil record seems clear; there is little or no evidence that entire groups of plants moved north together. Things that lived together in the past don’t live together now, and things that live together now didn’t live together in the past. Each individual organism moved at its own pace. The fossil record seems to be telling us that we should be thinking about preserving species by giving them room to maneuver – to respond to environmental changes.

The word “which” in last sentence of paragraph 1 refers to _______.

A. the developments of ecosystems

B. plant life changes

C. the current theories of ecosystem

D. the responses of plants to climate changes

#Mẫu giáo

1

DH

Dương Hoàn Anh

17 tháng 5 2019

Kiến thức: Đọc hiểu

Giải thích:

Từ “which” ở câu cuối của đoạn 1 nhắc đến điều gì _______.

A. sự phát triển của hệ sinh thái B. sự thay đổi đời sống thực vật

C. các lý thuyết hiện đại về hệ sinh thái D. phản ứng của thực vật với biến đổi khí hậu

Thông tin: They build up a picture of how groups of plants have responded to climate changes and how ecosystems develop. But are these associations, which are real in the present, permanent?

Tạm dịch: Họ phác họa nên một bức tranh về cách các nhóm thực vật đã ứng phó với biến đổi khí hậu và cách các hệ sinh thái phát triển. Nhưng những mối quan hệ đang xảy ra trên thực tế này có kéo dài mãi mãi?

Chọn D

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LQ

Lê Quỳnh Anh

24 tháng 11 2019

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the question. Mountaineers have noted that as they climb, for example, up to the 12,633–foot Humphreys Peak in the San Francisco Peaks in Arizona, plant life changes radically. Starting among the cacti of the Sonoran Desert, one climbs into a pine forest at 7,000 feet and a treeless alpine tundra at the summit. It may seem that plants at a given altitude are associated in...

Đọc tiếp

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the question.

Mountaineers have noted that as they climb, for example, up to the 12,633–foot Humphreys Peak in the San Francisco Peaks in Arizona, plant life changes radically. Starting among the cacti of the Sonoran Desert, one climbs into a pine forest at 7,000 feet and a treeless alpine tundra at the summit. It may seem that plants at a given altitude are associated in what can be called “communities” – groupings of interacting species. The idea is that over time, plants that require particular climate and soil conditions come to live in the same places, and hence are frequently to be found together. Scientists who study the history of plant life are known as paleobotanists, or paleobots for short. They build up a picture of how groups of plants have responded to climate changes and how ecosystems develop. But are these associations, which are real in the present, permanent?

A great natural experiment took place on this planet between 25,000 and 10,000 years ago, when small changes in the earth’s orbit and axis of rotation caused great sheets of ice to spread from the poles. These glaciers covered much of North America and Europe to depths of up to two miles, and then, as the climate warmed, they retreated. During this retreat, they left behind newly uncovered land for living things to colonize, and as those living things moved in they laid down a record we can read now. As the ice retreated and plants started to grow near a lake, they would release pollen. Some would fall into the lake, sink to the bottom, and be incorporated into the sediment. By drilling into the lake bottom it is possible to read the record of successive plant life around the lake. The fossil record seems clear; there is little or no evidence that entire groups of plants moved north together. Things that lived together in the past don’t live together now, and things that live together now didn’t live together in the past. Each individual organism moved at its own pace. The fossil record seems to be telling us that we should be thinking about preserving species by giving them room to maneuver – to respond to environmental changes.

The word “successive” in paragraph 2 is closest in meaning to _______.

A. consecutive

B. accumulative

C. extinct

D. following

#Mẫu giáo

1

DH

Dương Hoàn Anh

24 tháng 11 2019

Kiến thức: Đọc hiểu

Giải thích:

successive = consecutive (adj): liên tục, kế tiếp accumulative (adj): chất đống, chồng chất

extinct (adj): tuyệt chủng following (adj): tiếp sau đó về thời gian

Thông tin: By drilling into the lake bottom it is possible to read the record of successive plant life around the lake.

Tạm dịch: Bằng cách khoan vào đáy hồ, có thể đọc được hồ sơ về đời sống thực vật kế tiếp quanh hồ.

Chọn A

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LQ

Lê Quỳnh Anh

22 tháng 11 2019

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the question. Mountaineers have noted that as they climb, for example, up to the 12,633–foot Humphreys Peak in the San Francisco Peaks in Arizona, plant life changes radically. Starting among the cacti of the Sonoran Desert, one climbs into a pine forest at 7,000 feet and a treeless alpine tundra at the summit. It may seem that plants at a given altitude are associated in...

Đọc tiếp

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the question.

Mountaineers have noted that as they climb, for example, up to the 12,633–foot Humphreys Peak in the San Francisco Peaks in Arizona, plant life changes radically. Starting among the cacti of the Sonoran Desert, one climbs into a pine forest at 7,000 feet and a treeless alpine tundra at the summit. It may seem that plants at a given altitude are associated in what can be called “communities” – groupings of interacting species. The idea is that over time, plants that require particular climate and soil conditions come to live in the same places, and hence are frequently to be found together. Scientists who study the history of plant life are known as paleobotanists, or paleobots for short. They build up a picture of how groups of plants have responded to climate changes and how ecosystems develop. But are these associations, which are real in the present, permanent?

A great natural experiment took place on this planet between 25,000 and 10,000 years ago, when small changes in the earth’s orbit and axis of rotation caused great sheets of ice to spread from the poles. These glaciers covered much of North America and Europe to depths of up to two miles, and then, as the climate warmed, they retreated. During this retreat, they left behind newly uncovered land for living things to colonize, and as those living things moved in they laid down a record we can read now. As the ice retreated and plants started to grow near a lake, they would release pollen. Some would fall into the lake, sink to the bottom, and be incorporated into the sediment. By drilling into the lake bottom it is possible to read the record of successive plant life around the lake. The fossil record seems clear; there is little or no evidence that entire groups of plants moved north together. Things that lived together in the past don’t live together now, and things that live together now didn’t live together in the past. Each individual organism moved at its own pace. The fossil record seems to be telling us that we should be thinking about preserving species by giving them room to maneuver – to respond to environmental changes.

The author mentions “cacti” and “a treeless alpine tundra” in paragraph 1 to illustrate _______.

A. changes in climate

B. the effects of the ice age

C. plant immigration

D. communities of plants

#Mẫu giáo

1

DH

Dương Hoàn Anh

22 tháng 11 2019

Kiến thức: Đọc hiểu

Giải thích:

Tác giả đã đề cập đến “xương rồng” và một “một lãnh nguyên núi cao” trong đoạn 1 để minh họa cho _______.

A. thay đổi khí hậu B. ảnh hưởng của kỷ băng hà

C. sự di cư của thực vật D. quần xã thực vật

Thông tin: Starting among the cacti of the Sonoran Desert, one climbs into a pine forest at 7,000 feet and a treeless alpine tundra at the summit. It may seem that plants at a given altitude are associated in what can be called “communities” – groupings of interacting species.

Tạm dịch: Bắt đầu giữa những cây xương rồng của sa mạc Sonoran, một người leo lên một khu rừng thông ở độ cao 7,000 feet và một lãnh nguyên núi cao vô tận ở đỉnh núi. Dường như các loài thực vật ở độ cao nhất định có liên quan đến những gì có thể được gọi là “quần xã” – nhóm các loài tương tác.

Chọn D

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LQ

Lê Quỳnh Anh

6 tháng 10 2019

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the question. Mountaineers have noted that as they climb, for example, up to the 12,633–foot Humphreys Peak in the San Francisco Peaks in Arizona, plant life changes radically. Starting among the cacti of the Sonoran Desert, one climbs into a pine forest at 7,000 feet and a treeless alpine tundra at the summit. It may seem that plants at a given altitude are associated in...

Đọc tiếp

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the question.

Mountaineers have noted that as they climb, for example, up to the 12,633–foot Humphreys Peak in the San Francisco Peaks in Arizona, plant life changes radically. Starting among the cacti of the Sonoran Desert, one climbs into a pine forest at 7,000 feet and a treeless alpine tundra at the summit. It may seem that plants at a given altitude are associated in what can be called “communities” – groupings of interacting species. The idea is that over time, plants that require particular climate and soil conditions come to live in the same places, and hence are frequently to be found together. Scientists who study the history of plant life are known as paleobotanists, or paleobots for short. They build up a picture of how groups of plants have responded to climate changes and how ecosystems develop. But are these associations, which are real in the present, permanent?

A great natural experiment took place on this planet between 25,000 and 10,000 years ago, when small changes in the earth’s orbit and axis of rotation caused great sheets of ice to spread from the poles. These glaciers covered much of North America and Europe to depths of up to two miles, and then, as the climate warmed, they retreated. During this retreat, they left behind newly uncovered land for living things to colonize, and as those living things moved in they laid down a record we can read now. As the ice retreated and plants started to grow near a lake, they would release pollen. Some would fall into the lake, sink to the bottom, and be incorporated into the sediment. By drilling into the lake bottom it is possible to read the record of successive plant life around the lake. The fossil record seems clear; there is little or no evidence that entire groups of plants moved north together. Things that lived together in the past don’t live together now, and things that live together now didn’t live together in the past. Each individual organism moved at its own pace. The fossil record seems to be telling us that we should be thinking about preserving species by giving them room to maneuver – to respond to environmental changes.

The passage states that by drilling into the lake bottom it is possible to find successive fossils of _______.

A. plant life

B. sediment

D. ice

D. pollen

#Mẫu giáo

1

DH

Dương Hoàn Anh

6 tháng 10 2019

Kiến thức: Đọc hiểu

Giải thích:

Đoạn văn nói rằng bằng cách khoan vào đáy hồ, có thể tìm thấy hóa thạch liên tiếp của _______.

A. đời sống thực vật B. trầm tích D. băng D. phấn hoa

Thông tin: As the ice retreated and plants started to grow near a lake, they would release pollen. Some would fall into the lake, sink to the bottom, and be incorporated into the sediment. By drilling into the lake bottom it is possible to read the record of successive plant life around the lake.

Tạm dịch: Khi băng tan và thực vật bắt đầu mọc gần hồ, chúng sẽ tỏa ra phấn hoa. Một số sẽ rơi xuống hồ, chìm xuống đáy và tạo thành trầm tích. Bằng cách khoan vào đáy hồ, người ta có thể đọc được sự phát triển của đời sống thực vật kế tiếp quanh hồ.

Chọn D

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LQ

Lê Quỳnh Anh

29 tháng 1 2018

Read the following passages and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions The biological community changes again as one moves from the city to the suburbs. Around all cities is a biome called the "suburban forest". The trees of this forest are species that are favored by man, and most of them have been deliberately planted. Mammals such as rabbits, skunks, and opossums have moved in from the surrounding countryside....

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#Mẫu giáo

1

DH

Dương Hoàn Anh

29 tháng 1 2018

Chọn đáp án A

Đâu diễn tả ý chính phù hợp nhất cho đoạn 2

A. quần xã sinh vật ở bờ biển phía đông và tây là khác nhau

B. rừng ngoại ô chiếm phần lớn quang cảnh Mĩ

C. những vùng ngoại ô ở Mĩ có sự giống nhau đáng kể với quần xã sinh vật

D. Sinh cảnh tự nhiên được nghiên cứu nhiều hơn sinh cảnh ngoại ô

Dịch đoạn 2: Có sự giống nhau kì lại về mặt sinh học trên những quần xa ngoại ô này. Thật vật, sự giàu tài nguyên sinh vật ở Los Angeles (The palms- is a highly diverse, densely populated community) đang mất dần từ Boston, và có những loài côn trùng ở Miami không được tìm thấy ở Seattle. Nhưng ở những vùng rộng lớn của Hoa Kỳ, các điều kiện sinh thái ở quần xã sinh vật ngoại ô biến đổi ít hơn nhiều so với quần xã sinh vật tự nhiên. Và không giống như quần xã sinh vật tự nhiên, cộng đồng sinh vật thành thị và ngoại ô tồn tại không bị ảnh hưởng bởi khí hậu)

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LQ

Lê Quỳnh Anh

22 tháng 4 2017

Read the passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions.The forest from which Man takes his timber is the tallest and most impressive plant community on Earth. In terms of Man’s brief life, it appears permanent and unchanging, save for the season growth and fall of the leaves, but to the forester, it represents the climax of a long succession of events.No wooded landscape we see today has been forest for all time. Plants have minimum...

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Read the passage and mark the letter A, B, C or D to indicate the correct answer to each of the questions.

The forest from which Man takes his timber is the tallest and most impressive plant community on Earth. In terms of Man’s brief life, it appears permanent and unchanging, save for the season growth and fall of the leaves, but to the forester, it represents the climax of a long succession of events.

No wooded landscape we see today has been forest for all time. Plants have minimum requirements of temperature and moisture and, in ages past, virtually every part of Earth’s surface has, at some time, been either too dry or too cool for plants to survive.

However, as soon as climatic conditions change in favor of plant life, a fascinating sequence of changes, called a primary succession, occurs first to colonize the barren land and the lichen surviving on bare rock. Slowly, the acids produced by these organisms crack the rock’s surface, plants debris accumulate and mosses establish shallow root-holes. Ferns may allow and, with short grasses and shrubs, gradually form a covering of plant life. Roots broke even deeper into the developing soil and eventually large shrubs give way to the first trees. These grow rapidly, cutting off sunlight from the smaller plants, and soon establish complete domination - closing their ranks and forming a climax community which may endure for thousands of years. Yet even this community is not everlasting. Fire may destroy it outright and settlers may cut it down to gain land for pasture or cultivations. If the land is then abandoned, a secondary succession will take over, developing much faster on the more hospitable soil. Shrubs and trees are among the early invaders, their seeds carried by the wind, by birds and lodged in the coat of mammals.

For as long as it stands and strives, the forest is a vast machine storing energy and the many elements essential for life.

What conditions are needed for shrubs to become established?

A. More soil must accumulate.

B. The ground must be covered with grass.

C. Smaller plants must die now.

D. Ferns must take root.

#Mẫu giáo

1

DH

Dương Hoàn Anh

22 tháng 4 2017

Đáp án là A.

Dựa vào ý: Roots broke even deeper into the developing soil. These grow rapidly, cutting off sunlight from the smaller plants, and soon establish complete domination - closing their ranks and forming a climax community which may endure for thousands of years

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LQ

Lê Quỳnh Anh

6 tháng 4 2019

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 38 to 42. The biological community changes again as one moves from the city to the suburbs. Around all cities is a biome called the "suburban forest". The trees of this forest are species that are favored by man, and most of them have been deliberately planted. Mammals such as rabbits, skunks, and opossums have moved in from the surrounding...

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#Mẫu giáo

1

DH

Dương Hoàn Anh

6 tháng 4 2019

Đáp án D

Kết luận nào về các loài sóc được chứng minh trong đoạn văn

A. Cuộc chiến giữa 3 loài rất căng thẳng

B. loài sóc cáo phổ biến hơn sóc xám và sóc đỏ

C. 2 loài sóc thỉnh thoảng cư trú cùng 1 vùng ngoại ô

D. lí do các loài sóc thích nghi tốt ở vùng ngoại ô nay vẫn chưa rõ

Dẫn chứng: “ but usually only one species is predominant in any given suburb -fox squirrels in one place, red squirrels in another, gray squirrels in a third– for reasons that are little understood”-gần cuối đoạn 1

(…nhưng chỉ có 1 loài là chiếm ưu thế trong bất kì khu vực ngoại ô nào đó- loài sóc cáo ở 1 vùng, sóc đỏ ở 1 vùng khác, sóc xám ở 1 vùng thứ 3. -lí do này nay vẫn chưa giải thích được)

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