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26 tháng 3 2018

Đáp án A So sánh hơn của trạng từ ngắn (fast): S + V + adv-er + than + S + do/does

15 tháng 3 2019

Đáp án A

Giải thích: Khi so sánh, vế sau than phải dùng đúng cấu trúc như về trước (ví dụ He drives faster than I drive/ He is taller than I am), tuy nhiên có thể tránh lặp bằng cách thay động từ bằng trợ động từ tương ứng, to be thì giữ nguyên.

Dịch nghĩa: Mặc dù sấm và chớp được tạo ra cùng một lúc, nhưng sóng ánh sáng đi nhanh hơn sóng âm thanh nên ta nhìn thấy chớp trước khi nghe thấy sấm.

9 tháng 1 2019

Chọn C

Câu đề bài: “Mặc dù sấm và sét được tạo ra cùng một lúc, sóng ánh sáng đi xa hơn___________, vì vậy chúng ta thấy sét trước khi chúng ta nghe thấy sấm ".

Đáp án C: than sound waves do

—» Đây là cách nói rút gọn của “than sound waves travel”: cấu trúc so sánh hơn kém:

S + V + trạng từ ngắn đuôi er/dài thêm more + than + S + V.

9 tháng 1 2017

Chọn C                                 Câu đề bài: “Mặc dù sấm và sét được tạo ra cùng một lúc, sóng ánh sáng đi xa hơn___________, vì vậy chúng ta thấy sét trước khi chúng ta nghe thấy sấm ".

Đáp án C: than sound waves do

—» Đây là cách nói rút gọn của “than sound waves travel”: cấu trúc so sánh hơn kém:

S + V + trạng từ ngắn đuôi er/dài thêm more + than + S + V.

Read the passage and choose the best answer.A pilot cannot fly by sight alone. In many conditions, such as flying at night and landing in dense fog, a pilot must use radar, an alternative way of navigating. Since human eyes are not very good at determining speeds of approaching objects, radar can show a pilot how fast nearby planes are moving. The basic principle of radar is exemplified by what happens when one shouts in a cave. The echo of the sounds against the walls helps a person determine...
Đọc tiếp

Read the passage and choose the best answer.

A pilot cannot fly by sight alone. In many conditions, such as flying at night and landing in dense fog, a pilot must use radar, an alternative way of navigating. Since human eyes are not very good at determining speeds of approaching objects, radar can show a pilot how fast nearby planes are moving. The basic principle of radar is exemplified by what happens when one shouts in a cave. The echo of the sounds against the walls helps a person determine the size of the cave. With radar, however, the waves are radio waves instead of sound waves. Radio waves travel at the speed of light, about 300,000 kilometers in one second. A radar set sends out a short burst of radio waves. Then it receives the echoes produced when the waves bounce off objects. By determining the time it takes for the echoes to return to the radar set, a trained technician can determine the distance between the radar set and other objects. The word “radar”, in fact, gets its name from the term “radio detection and ranging”. “Ranging” is the term for detection of the distance between an object and the radar set. Besides being of critical importance to pilots, radar is essential for air traffic control, tracking ships at sea, and for tracking weather systems and storms. 

Which type of waves does radar use?  

A. tidal

B. sound 

C. heat 

D. radio

1
21 tháng 11 2018

Dựa vào “With radar, however, the waves are radio waves instead of sound waves.”

Đáp án  D

Read the passage and choose the best answer.A pilot cannot fly by sight alone. In many conditions, such as flying at night and landing in dense fog, a pilot must use radar, an alternative way of navigating. Since human eyes are not very good at determining speeds of approaching objects, radar can show a pilot how fast nearby planes are moving. The basic principle of radar is exemplified by what happens when one shouts in a cave. The echo of the sounds against the walls helps a person determine...
Đọc tiếp

Read the passage and choose the best answer.

A pilot cannot fly by sight alone. In many conditions, such as flying at night and landing in dense fog, a pilot must use radar, an alternative way of navigating. Since human eyes are not very good at determining speeds of approaching objects, radar can show a pilot how fast nearby planes are moving. The basic principle of radar is exemplified by what happens when one shouts in a cave. The echo of the sounds against the walls helps a person determine the size of the cave. With radar, however, the waves are radio waves instead of sound waves. Radio waves travel at the speed of light, about 300,000 kilometers in one second. A radar set sends out a short burst of radio waves. Then it receives the echoes produced when the waves bounce off objects. By determining the time it takes for the echoes to return to the radar set, a trained technician can determine the distance between the radar set and other objects. The word “radar”, in fact, gets its name from the term “radio detection and ranging”. “Ranging” is the term for detection of the distance between an object and the radar set. Besides being of critical importance to pilots, radar is essential for air traffic control, tracking ships at sea, and for tracking weather systems and storms. 

 According to the passage, the distance between a radar set and an object can be determined by _______.  

A. the time it takes for a burst of radio waves to produce echoes when the waves bounce off the object 

B. the term “ranging” used for detection of the distance between an object and the radar set 

C. the time it takes for the radio waves to produce echoes and bounce off the object 

D. the time it takes for the echoes produced by the radio waves to return to the radar set

1
13 tháng 12 2018

Giải thích: Dựa vào “The echo of the sounds against the walls helps a person determine the size of the cave.”

Đáp án  D

Read the passage and choose the best answer.A pilot cannot fly by sight alone. In many conditions, such as flying at night and landing in dense fog, a pilot must use radar, an alternative way of navigating. Since human eyes are not very good at determining speeds of approaching objects, radar can show a pilot how fast nearby planes are moving. The basic principle of radar is exemplified by what happens when one shouts in a cave. The echo of the sounds against the walls helps a person determine...
Đọc tiếp

Read the passage and choose the best answer.

A pilot cannot fly by sight alone. In many conditions, such as flying at night and landing in dense fog, a pilot must use radar, an alternative way of navigating. Since human eyes are not very good at determining speeds of approaching objects, radar can show a pilot how fast nearby planes are moving. The basic principle of radar is exemplified by what happens when one shouts in a cave. The echo of the sounds against the walls helps a person determine the size of the cave. With radar, however, the waves are radio waves instead of sound waves. Radio waves travel at the speed of light, about 300,000 kilometers in one second. A radar set sends out a short burst of radio waves. Then it receives the echoes produced when the waves bounce off objects. By determining the time it takes for the echoes to return to the radar set, a trained technician can determine the distance between the radar set and other objects. The word “radar”, in fact, gets its name from the term “radio detection and ranging”. “Ranging” is the term for detection of the distance between an object and the radar set. Besides being of critical importance to pilots, radar is essential for air traffic control, tracking ships at sea, and for tracking weather systems and storms. 

 Which of the following would most likely be the topic of the next paragraph?  

A. A history of flying.

B. Other uses of radar. 

C. The technology used by pilots. 

D. Uses of some technology.

1
10 tháng 1 2018

Giải thích: Sauk hi giải thích về bản chất của radar thì hẳn nhiên phần sau (nếu có) của bài viết sẽ nói tiếp về radar, đặc biệt là các công dụng của nó.

Đáp án  B

Read the passage and choose the best answer.A pilot cannot fly by sight alone. In many conditions, such as flying at night and landing in dense fog, a pilot must use radar, an alternative way of navigating. Since human eyes are not very good at determining speeds of approaching objects, radar can show a pilot how fast nearby planes are moving. The basic principle of radar is exemplified by what happens when one shouts in a cave. The echo of the sounds against the walls helps a person determine...
Đọc tiếp

Read the passage and choose the best answer.

A pilot cannot fly by sight alone. In many conditions, such as flying at night and landing in dense fog, a pilot must use radar, an alternative way of navigating. Since human eyes are not very good at determining speeds of approaching objects, radar can show a pilot how fast nearby planes are moving. The basic principle of radar is exemplified by what happens when one shouts in a cave. The echo of the sounds against the walls helps a person determine the size of the cave. With radar, however, the waves are radio waves instead of sound waves. Radio waves travel at the speed of light, about 300,000 kilometers in one second. A radar set sends out a short burst of radio waves. Then it receives the echoes produced when the waves bounce off objects. By determining the time it takes for the echoes to return to the radar set, a trained technician can determine the distance between the radar set and other objects. The word “radar”, in fact, gets its name from the term “radio detection and ranging”. “Ranging” is the term for detection of the distance between an object and the radar set. Besides being of critical importance to pilots, radar is essential for air traffic control, tracking ships at sea, and for tracking weather systems and storms. 

 The word “shouts” in the passage most closely means _______.  

A. “exclaims”

B. “yells” 

C. “shoots” 

D. “whispers”

1
13 tháng 9 2017

Giải thích: Shout = Yell: La hét

Đáp án  B

Read the passage and choose the best answer.A pilot cannot fly by sight alone. In many conditions, such as flying at night and landing in dense fog, a pilot must use radar, an alternative way of navigating. Since human eyes are not very good at determining speeds of approaching objects, radar can show a pilot how fast nearby planes are moving. The basic principle of radar is exemplified by what happens when one shouts in a cave. The echo of the sounds against the walls helps a person determine...
Đọc tiếp

Read the passage and choose the best answer.

A pilot cannot fly by sight alone. In many conditions, such as flying at night and landing in dense fog, a pilot must use radar, an alternative way of navigating. Since human eyes are not very good at determining speeds of approaching objects, radar can show a pilot how fast nearby planes are moving. The basic principle of radar is exemplified by what happens when one shouts in a cave. The echo of the sounds against the walls helps a person determine the size of the cave. With radar, however, the waves are radio waves instead of sound waves. Radio waves travel at the speed of light, about 300,000 kilometers in one second. A radar set sends out a short burst of radio waves. Then it receives the echoes produced when the waves bounce off objects. By determining the time it takes for the echoes to return to the radar set, a trained technician can determine the distance between the radar set and other objects. The word “radar”, in fact, gets its name from the term “radio detection and ranging”. “Ranging” is the term for detection of the distance between an object and the radar set. Besides being of critical importance to pilots, radar is essential for air traffic control, tracking ships at sea, and for tracking weather systems and storms. 

 The word “exemplified” in the passage can be replaced by _______.  

A. “specified”

B. “resembled” 

C. “illustrated” 

D. “justified”

1
4 tháng 9 2019

Giải thích: exemplify = illustrate: Lấy ví dụ cho cái gì

Đáp án  C