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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.Atomic were once thought to be fundamental pieces of matter, but they are in turn made of smaller subatomic particles. There are three major subatomic particles neutrons, protons, and electronic. Protons and neutrons can be broken into even smaller units, but these smaller units do not occur naturally in nature and are thought to only be produced in manmade...
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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.

Atomic were once thought to be fundamental pieces of matter, but they are in turn made of smaller subatomic particles. There are three major subatomic particles neutrons, protons, and electronic. Protons and neutrons can be broken into even smaller units, but these smaller units do not occur naturally in nature and are thought to only be produced in manmade particle accelerators and perhaps in extreme stellar events like supernovas. The structure of an atom can best be described as a small solar system, with the neutrons at the center and the electrons circling them in various orbits, just as the planets circle the sun .In reality, the structure of an atom is far more complex, because the laws of physics are fundamentally different at the atomic level than of the level of the observable word. The true nature of atomic structure can only be expressed accurately through complex mathematical formulas .This explanation, however, is of little use to most average people.

Protons and neutrons have nearly equal mass and size, but protons carry a positive electrical charge, while neutrons carry no charge at all. Protons and neutrons are bound together by the strong nuclear force, one of the four basic forces in the universe. Protons and neutrons give atoms some of their most basic properties. Elements are defined by two numbers; their atomic number , which is equal to the number of protons they have, and their atomic weight , which is equal to total number of their neutrons and protons. In most lighter atoms , the number of neutrons and protons is equal , and the element is stable. In heavier atoms, however, there are more neutrons than protons , and the element is unstable, eventually losing neutrons through radioactive decay until a neutral state is reached.

Electrons are negatively charged particles. They are bound to their atoms through electromagnetic attraction. Opposite electrical charges attract one another, so the positive charge of the proton helps keep the negatively charged electron in orbit around the nucleus of the atom. Electrons are different from neutrons in that they cannot be broken down into smaller particles. They are also far smaller and lighter than neutrons and protons. An electron is about one thousandth of the diameter of a proton and an even smaller fraction of its mass. Electrons circle the protons and neutrons at the center of the atom in orbit. These orbits are often called electron shells. The closer the orbit is to the center of the atom, the lower its energy is. There are seven electron shells, and each higher level can hold more electron than the previous shell. Electrons naturally seek to occupy the lowest shell possible .So if there is space in a lower shell, an electron will drop down to occupy that space. At temperatures higher than a few hundred degrees, electrons will gain energy and move to a higher shell, but only momentarily. When the electrons drop back down to their natural shell, they emit light .This is why fires and other very hot objects seem to glow.

Electrons are also primarily responsible for many of the chemical properties of atoms. Since electrons seek to occupy the lowest electron shell possible, they will move from one atom to another if there is a space available in a lower electron shell. For example, if there is an atom with an open space in its third shell, and it comes into contact with an atom with electrons in its fourth shell, the first atom will take one of these electrons to complete its third shell. When this happens, the two atoms will be chemically bonded to form a molecule. Furthermore, atoms sometimes lose electrons in collisions with other atoms. When it happens, the radio of protons and electrons in the atom changes, and therefore, the overall electrical charge of the atom changes as well. These atoms are called isotopes, and they have significantly different chemical properties from their parent atoms.

According to the passage, all of the following are true of electrons EXCEPT

A. Their energy levels are fixed and unchanging

B. They are kept in orbit by electromagnetic attraction

C. They are elementary particles and cannot be broken down

D. They are considerably smaller than neutrons or protons

1
22 tháng 9 2018

Đáp án là A

Theo bài đọc, tất cả những ý nào sau đây đúng về electron NGOẠI TRỪ

A. Mức năng lượng của chúng là cố định và không đổi.

B. Chúng được giữ trong quỹ đạo bởi những lực hấp dẫn mang điện cực.

C. Chúng là những phân tử cơ bản và không thể bị phá vỡ

D. Chúng nhỏ hơn rất nhiều so với các notron và proton.

Dẫn chứng:

They are bound to their atoms through electromagnetic attraction. =>loại B

Electrons are different from neutrons in that they cannot be broken down into smaller particles. => loại C và D

26 tháng 9 2019

Đáp án: D

Giải thích: Mấu chốt của câu này là các em phải đọc hết đoạn cuối để suy ra cái mà tác giả muốn hướng tới: Con người phải đối mặt với sự lựa chọn khó khăn: sự sống của mình hay cứu lấy động vật.

6 tháng 1 2017

Đáp án C.

Key words: Scott Joplin, Bessie Smith.

Clue: “Many musicians today credit earlier musicians such as Scott Joplin or Bessie Smith with inspiring their music”: Nhiều nhạc sĩ ngày nay ghi nhận những cái tên đi trước như Scott Joplin hay Bessie Smith vì những nghệ sĩ này đã truyền cảm hứng sáng tác cho họ.

Vậy đáp án đúng phải là C. artists who inspired many musicians today.

26 tháng 12 2018

Đáp án C.

Key words: Scott Joplin, Bessie Smith.

Clue: “Many musicians today credit earlier musicians such as Scott Joplin or Bessie Smith with inspiring their music”: Nhiều nhạc sĩ ngày nay ghi nhận những cái tên đi trước như Scott Joplin hay Bessie Smith vì những nghệ sĩ này đã truyền cảm hứng sáng tác cho họ.

Vậy đáp án đúng phải là C. artists who inspired many musicians today.

6 tháng 10 2019

Đáp án C.

Key words: Scott Joplin, Bessie Smith.

Clue: “Many musicians today credit earlier musicians such as Scott Joplin or Bessie Smith with inspiring their music”: Nhiều nhạc sĩ ngày nay ghi nhận những cái tên đi trước như Scott Joplin hay Bessie Smith vì những nghệ sĩ này đã truyền cảm hứng sáng tác cho họ.

Vậy đáp án đúng phải là C. artists who inspired many musicians today.

30 tháng 5 2019

Đáp án A

Refuse + to V = từ chối làm gì

Avoid + V-ing = tránh làm gì

Deny + V-ing = phủ nhận làm gì     

Bother + to V = phiền làm gì

→ Dùng “refused” để phù hợp ngữ cảnh

Dịch: Bộ trưởng từ chối cho ý kiến liệu tất cả các mỏ than sẽ bị đóng.

19 tháng 4 2017

Đáp án: D

Giải thích: Ở đoạn 4, tác giả nêu ra 3 điều kiện để tiếng lóng được tạo ra, trong đó không có điều kiện nêu ở câu 4 là một số lượng lớn nhà ngôn ngữ học.

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.American foods began to affect the rest of the world. American emphasis on convenient and rapid consumption is best represented in fast foods such as hamburgers, French fries, and soft drinks. By the 1960s and 1970s fast foods became one of America’s strongest exports as franchises for Mc Donald’s and Burger King spread through Europe and other parts of the...
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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.

American foods began to affect the rest of the world. American emphasis on convenient and rapid consumption is best represented in fast foods such as hamburgers, French fries, and soft drinks. By the 1960s and 1970s fast foods became one of America’s strongest exports as franchises for Mc Donald’s and Burger King spread through Europe and other parts of the world, including Russia and China. Traditional meals cooked at home and consumed at a leisurely pace gave way to quick lunches and dinners eaten on the run as other countries imitated American cultural patterns.

By the late 20th century Americans had become more conscious of their diets, eating more poultry, fish and vegetables, and fewer eggs and less beef. Cooks began to rediscover many world cuisines in forms closer to their original. In California, chefs combined fresh fruits and vegetables available with ingredients and spices borrowed from immigrant kitchens to create an innovative cooking style that was lighter than traditional French, but more interesting and varied than typical American cuisine. Along with the state’s wines, California cuisine took its place among the acknowledged forms of fine dining.

Question 28. Fast foods such as hamburgers, French fries, and soft drinks_________.

A. are popular because of their nutritious values 

B. are traditional meals of the US people

C. became more popular than meals cooked at home in China.

D. became popular with other European and Asian countries

Question 29. Which of the following is similar in meaning to the word ‘cuisine’?

A. cooking B. cooker C. cookery D. cook

Question 30. What is the main idea of the first paragraph? 

A.America’s cuisine used to have an influence on many countries. 

B. Fast foods became one of America’s strongest exports.

C. Mc Donald’s and Burger King are American food suppliers successful in Europe. 

D. Traditional meals cooked at home are not common in the US. 

Question 31. Which of the following statements is true? 

A. By the late 20th century, fast foods had lost their popularity in the US. 

B. Americans used to eat more poultry, fish, fruits and vegetables than they do now.

C. Cooking styles of other countries began to affect Americans by the late 20th century. 

D. Fewer eggs and less beef in American diet made them fitter.

Question 32. An innovative style of cooking was created in California_________.

A. to attract more immigrants to the state

B. and made the states wines well-known

C. by borrowing recipes from immigrant kitchens 

D. by combining the local specialties with immigrants’ spices

1
19 tháng 1 2022

Question 28. Fast foods such as hamburgers, French fries, and soft drinks_________.

A. are popular because of their nutritious values 

B. are traditional meals of the US people

C. became more popular than meals cooked at home in China.

D. became popular with other European and Asian countries

Question 29. Which of the following is similar in meaning to the word ‘cuisine’?

A. cooking B. cooker C. cookery D. cook

Question 30. What is the main idea of the first paragraph? 

A.America’s cuisine used to have an influence on many countries. 

B. Fast foods became one of America’s strongest exports.

C. Mc Donald’s and Burger King are American food suppliers successful in Europe. 

D. Traditional meals cooked at home are not common in the US. 

Question 31. Which of the following statements is true? 

A. By the late 20th century, fast foods had lost their popularity in the US. 

B. Americans used to eat more poultry, fish, fruits and vegetables than they do now.

C. Cooking styles of other countries began to affect Americans by the late 20th century. 

D. Fewer eggs and less beef in American diet made them fitter.

Question 32. An innovative style of cooking was created in California_________.

A. to attract more immigrants to the state

B. and made the states wines well-known

C. by borrowing recipes from immigrant kitchens 

D. by combining the local specialties with immigrants’ spices

31 tháng 5 2019

Đáp án: C

Giải thích: obscurity: the state in which sb/sth is not well known or has been forgotten (trạng thái bị lãng quên/không nổi tiếng) = disappearance: sự biến mất.

28 tháng 7 2017

Đáp án là D

Kiến thức: Sự hòa hợp giữa chủ ngữ và động từ

Trong câu đã có động từ “ were” => câu cần chủ ngữ số nhiều

=>Chọn D

Câu này dịch như sau: Các điệu khiêu vũ của người Ai Cập cổ đại, thường thuộc về một nhân vật tôn giáo nào đó, được phát triển từ các dạng cơ bản của người châu Phi

31 tháng 10 2018

Đáp án B

Giải thích

work on a night shift: làm ca đêm

Dịch: Cha của tôi phải làm ca đêm tuần một lầ