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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 following questions                                The ability to conduct electricity is one of the key properties of  a metal. Other solid material such as silicon can conduct electricity but only effectively at certain temperatures. Also, some substances such as salt (sodium chloride) can conduct when molten or when dissolved  in water. The ability of metals to...
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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 following questions                               

The ability to conduct electricity is one of the key properties of  a metal. Other solid material such as silicon can conduct electricity but only effectively at certain temperatures. Also, some substances such as salt (sodium chloride) can conduct when molten or when dissolved  in water. The ability of metals to conduct electricity is due to how their atoms bond together. In order to bond together the metal atoms lose at least one of their outermost  electrons. This leaves the metal atoms with a positive charge and they are now strictly  ions. The lost electrons are free to move in what are known  as a sea of electrons. Since the electrons are negatively charged they attract the ions and this is what keeps the structure together.

            An electric current is a flow of charge and since the electrons in the sea of electrons are free to move they can be made to flow in one direction when a source of electrical energy such as a battery is connected to the metal. Hence we have an electric current flowing through the wire, and this is what makes metals such good conductors of electricity. The only other common solid conducting material that pencil users are likely to encounter is graphite (what the ‘lead’ of a pencil is made from). Graphite is a form of carbon and again the carbon atoms bond in such a way that there is a sea of electrons that can be made to flow as an electric current. Likewise, if we have an ionic substance like salt we can make the electrically charged ions flow to create a current but only when those ions are free to move, either when the substance is a liquid or dissolved in water. In its solid state an ionic substance like salt cannot conduct electricity as its charged ions cannot flow. Freshwater Aquarium Fish

Playlist Freshwater Aquarium Fish

       Electrical insulators are substances that cannot conduct electricity well either, because they contain no charged particles or any charged particles they might contain do not flow easily. Water itself is a poor conductor or electricity as it does not contain a significant amount of fully charged particles (the ends of a water molecule are partly charged but overall the molecule is neutral). However, most water we encounter does contain dissolved charged particles, so it will be more conductive than pure water. Many of the problems that occur when touching electrical devices with wet hands result from the ever-present salt that is left on our skin through perspiration and it dissolves in the water to make it more conductive.

By Helena Gillespie and Rob Gillespie. Science for Primary School Teacher. OUP

Which of the following is NOT true according to the passage?

A. . Pure water is much more conductive than most water we encounter every day. 

B. Graphite is a common solid substance that can conduct electricity. 

C. Salt can conduct electricity when it is molten or dissolved. 

D. Some materials are more conductive than others.

1
19 tháng 1 2018

Đáp án : A

Dòng 5 đoạn cuối: most water we encounter does contain dissolved charged particles, so it will be more conductive than pure water -> nước chứa các phần tử mang điện không hòa tan dẫn điện hơn nước nguyên chất

9 tháng 10 2017

Đáp án A

Kiến thức: Chức năng giao tiếp

Giải thích: Lễ tân: “ Chào buổi sáng.”

Chris: “ Chào buổi sáng. Tôi đến để gặp bà Dabria”.

see (v): nhìn visit (v): thăm, gặp

do business with: kinh doanh với hold a talk with: nói chuyện

3 tháng 11 2018

Đáp án B

Kiến thức: Từ loại, sửa lại câu

Giải thích:

planning => plan

Vị trí này ta cần một danh từ, vì phía trước có mạo từ “a” và tính từ “comprehensive”

Tạm dịch: Cán cán bộ trong trường học đang xem xét một kế hoạch toàn diện để làm giảm bớt vấn đề quá tải trong ký túc xá.

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 below.We find that bright children are rarely held back by mixed-ability teaching. On the contrary, both their knowledge and experience are enriched. We feel that there are many disadvantages in streaming pupils. It does not take into account the fact that children develop at different rates. It can have a bad effect on both the bright and the not-so-bright...
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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 question below.

We find that bright children are rarely held back by mixed-ability teaching. On the contrary, both their knowledge and experience are enriched. We feel that there are many disadvantages in streaming pupils. It does not take into account the fact that children develop at different rates. It can have a bad effect on both the bright and the not-so-bright child. After all, it can be quite discouraging to be at the bottom of the top grade!

Besides, it is rather unreal to grade people just according to their intellectual ability. This is only one aspect of their total personality. We are concerned to develop the abilities of all our pupils to the full, not just their academic ability. We also value personal qualities and social skills, and we find that mixed-ability teaching contributes to all these aspects of learning.

In our classroom, we work in various ways. The pupils often work in groups; this gives them the opportunity to learn to co-operate, to share, and to develop leadership skills. They also learn how to cope with the personal problems as well as learning how to think, to make decisions, to analyze and evaluate, to communicate effectively. The pupils learn from each other as well as from the teachers.

Sometimes the pupils work in pairs; sometimes the work on individual tasks and assignments, they can do this at their own speed. They also have some formal class teaching when this is appropriate. We encourage our pupils to use the library, and we teach them the skills they need in order to do this effectively. An advanced pupil can do advanced works; it does not matter what age the child is. We expect our pupils to do their best, not their least, and we give them every encouragement to attain this goal

In the passage, the author’s attitude towards “mixed-ability teaching” is ________

A. questioning

B. approving

C. objective

D. critical

1
4 tháng 3 2018

Đáp án : B

Trong đoạn mở đầu, tác giả cho rằng những đứa trẻ tài giỏi không bị cản trở bởi khả năng dạy hỗn hợp của giáo viên; mà ngược lại còn có thêm kiến thức và kinh nghiệm học tập (rarely held back by mixed-ability teaching. On the contrary, both their knowledge and experience are enriched) -> tác giả đồng tình với khả năng dạy hỗn hợp (approving)

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 35 to 42.Life in the UniverseExobiology is the study of life that originates from outside of Earth. As yet, of course, no such life forms have been found. Exobiologists, however, have done important work in the theoretical study of where life is most likely to evolve, and what those extrateưestrial life forms might be like.What sorts of planets are most...
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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 from 35 to 42.

Life in the Universe

Exobiology is the study of life that originates from outside of Earth. As yet, of course, no such life forms have been found. Exobiologists, however, have done important work in the theoretical study of where life is most likely to evolve, and what those extrateưestrial life forms might be like.

What sorts of planets are most likely to develop life? Most scientists agree that a habitable planet must be terrestrial, or rock-based, with liquid surface water and biogeochemical cycles that somewhat resemble Earth’s. Water is an important solvent involved in many biological processes. Biogeochemical cycles are the continuous movement and transformation of materials in the environment. These cycles include the circulation of elements and nutrients upon which life and the Earth’s climate depend. Since (as far as we know) all life is carbon-based, a stable carbon cycle is especially important.

The habitable zone is the region around a star in which planets can develop life. Assuming the need for liquid surface water, it follows that most stars around the size of our sun will be able to sustain habitable zones for billions of years. Stars that are larger than the sun are much hotter and bum out more quickly; life there may not have enough time to evolve. Stars that are smaller than the sun have different problem. First of all, planets in their habitable zones will be so close to the star that they will be “tidally locked” – that is one side of the planet will always face the star in perpetual daylight with the other side in the perpetual night. Another possible obstacle to life on smaller stars is that they tend to vary in their luminosity, or brightness, due to flares and “star spots”. The variation can be large enough to have harmful effects on the ecosystem.

Of course, not all stars of the right size will give rise to life; they also must have terrestrial planets with the right kind of orbits. Most solar systems have more than one planet, which influence each other’s orbits with their own gravity. Therefore, in order to have a stable system with no planets flying out into space, the orbits must be a good distance from one another. Interestingly, the amount of space needed is roughly the width of a star’s habitable zone. This means that for life to evolve, the largest possible number of life-supporting planets in any star’s habitable zone is two.

Finally, not all planets meeting the above conditions will necessarily develop life. One major threat is large, frequent asteroid and comet impacts, which will wipe out life each time it tries to evolve. The case of Earth teaches that having large gas giants, such as Saturn and Jupiter,.in the outer part of the solar system can help keep a planet safe for life. Due to their strong gravitation, they tend to catch or deflect large objects before they can reach Earth.
Question:
It can be inferred from paragraph 4 that

A. most stars have more than two planets in their habitable zones

B. no star has more than two planets in its habitable zone

C. it is not possible for a star to have three planets with life on them

D. for life to develop, a star must have at least two planets in its habitable zone

1
15 tháng 8 2017

Đáp án C

Kiến thức: Đọc hiểu

Giải thích:

Có thể rút ra từ đoạn 4 rằng…

A. hầu hết các ngôi sao có nhiều hơn 2 hành tinh trong khu vực có thể sống của họ

B. không có ngôi sao nào có nhiều hơn 2 hành tinh trong khu vực có thể sống của nó

C. không có khả năng cho 1 ngôi sao có 3 hành tinh cùng chúng.

D. để sự sống phát triển, một ngôi sao phải có ít nhất 2 hành tinh trong khu vực có thể sống của nó

Thông tin: This means that for life to evolve, the largest possible number of life­supporting planets in any star’s habitable zone is two.

Tạm dịch: Điều này có nghĩa là để sự sống phát triển, số lượng lớn nhất để hỗ trợ các hành tinh trong khu vực có thể sống của một ngôi sao là 2.

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 below.We find that bright children are rarely held back by mixed-ability teaching. On the contrary, both their knowledge and experience are enriched. We feel that there are many disadvantages in streaming pupils. It does not take into account the fact that children develop at different rates. It can have a bad effect on both the bright and the not-so-bright...
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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 question below.

We find that bright children are rarely held back by mixed-ability teaching. On the contrary, both their knowledge and experience are enriched. We feel that there are many disadvantages in streaming pupils. It does not take into account the fact that children develop at different rates. It can have a bad effect on both the bright and the not-so-bright child. After all, it can be quite discouraging to be at the bottom of the top grade!

Besides, it is rather unreal to grade people just according to their intellectual ability. This is only one aspect of their total personality. We are concerned to develop the abilities of all our pupils to the full, not just their academic ability. We also value personal qualities and social skills, and we find that mixed-ability teaching contributes to all these aspects of learning.

In our classroom, we work in various ways. The pupils often work in groups; this gives them the opportunity to learn to co-operate, to share, and to develop leadership skills. They also learn how to cope with the personal problems as well as learning how to think, to make decisions, to analyze and evaluate, to communicate effectively. The pupils learn from each other as well as from the teachers.

Sometimes the pupils work in pairs; sometimes the work on individual tasks and assignments, they can do this at their own speed. They also have some formal class teaching when this is appropriate. We encourage our pupils to use the library, and we teach them the skills they need in order to do this effectively. An advanced pupil can do advanced works; it does not matter what age the child is. We expect our pupils to do their best, not their least, and we give them every encouragement to attain this goal

According to the passage, “streaming pupils”  ______

A. is the act of putting pupils into class according to their academic abilities

B. aims at enriching both their knowledge and experience

C. is quite discouraging

D. will help the pupils learn best

1
8 tháng 11 2018

Đáp án : A

Stream (v) có thể mang nghĩa: đưa học sinh vào các lớp theo trình độ của mình

12 tháng 11 2017

Đáp án A

Kiến thức: Giới từ

Giải thích:

among : ở giữa (trong số bao nhiêu đó) about: khoảng

Tạm dịch: Ở Mỹ khoảng 60% không gian của các trang báo dành chỗ cho quảng cáo.

among => about

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 following questionsThroughout history people have always communicated with one another, not only by speech but also by movements of the hands and body. It is, however, only (42) ______ the last few years that these aspects of communication have been studied at all widely. This type of communication is known as body language or non-verbal communication.People sometimes...
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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 following questions

Throughout history people have always communicated with one another, not only by speech but also by movements of the hands and body. It is, however, only (42) ______ the last few years that these aspects of communication have been studied at all widely. This type of communication is known as body language or non-verbal communication.

People sometimes wonder (43) ______ you can learn how body language works. It is of course possible to read books on the subject but you also need to (44) ______ time observing people’s movements. A railway station is a particular good place for such observation, as here people can be seen openly expressing eagerness, sorrow, delight, impatience and many other human emotions by (45) _____ of movement.

If you turn down the sound on your television set and try to understand (46) _____ is happening simply by watching the picture you will learn even more about communication (47) _____ words. By turning the sound back up every five (48) ______ or so, it is possible to check how accurate your (49) ______ is.

Having studied the art of body language you will have a definite (50) ______ at a boring party. You will be able to sit on your own for the whole evening and thoroughly enjoy yourself by both watching (51) ______ interpreting the body language of all the other people there.Question 47

A. and

B. including

C. without

D. with

1
21 tháng 10 2017

Đáp án : C

Without N = mà không có cái gì

Read the following passage on transport, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50. (1) The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm, constitute a classification of the most primitive forms of animal life. They are fantastically diverse, but three major groups may be identified on the basis of their motility. The Mastigophora have one or more long tails, which...
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Read the following passage on transport, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 43 to 50.

(1) The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm, constitute a classification of the most primitive forms of animal life. They are fantastically diverse, but three major groups may be identified on the basis of their motility. The Mastigophora have one or more long tails, which they use to project themselves forward. The Ciliata, which use the same basic means for locomotion as the Mastigophora, have a larger number of short tails. The Sarcodina, which include amoebae, float or row themselves about on their crusted bodies.

(2) In addition to their form of movement, several other features discriminate among the three groups of protozoans. For example, at least two nuclei per cell have been identified in the Ciliata, usually a large nucleus that regulates growth but decomposes during reproduction, and a smaller one that contains the genetic code necessary to generate the large nucleus.

(3) Protozoans are considered animals because, unlike pigmented plants to which some protozoans are otherwise almost identical, they do not live on simple organic compounds. Their cell demonstrates all of the major characteristics of the cells of higher animals.

(4) Many species of protozoans collect into colonies, physically connected to each other and responding uniformly to outside stimulate. Current research into this phenomenon, along with investigations carried out with advanced microscopes may necessitate a redefinition of what constitutes protozoans, even calling into question the basic premise that they have only one cell. Nevertheless, with the current data available, almost 40,000 species of protozoans have been identified. No doubt, as the technology improves our methods of observation, better models of classification will be proposed.

Which of the following statements are NOT true of protozoans?

(A) There are approximately 40,000 species.

(B) They are the most primitive forms of animal life.

(C) They have a large cell and a smaller cell.

(D) They are difficult to observe.

1
30 tháng 10 2019

Đáp án C

A: (4) Nevertheless, with the current data available, almost 40,000 species of protozoans have been identified.

B: (1) The protozoans, minute, aquatic creatures each of which consists of a single cell of protoplasm, constitute a classification of the most primitive forms of animal life

D: (4) No doubt, as the technology improves our methods of observation, better models of classification will be proposed.

Dịch bài

(1) Sinh vật đơn bào, loài sinh vật nhỏ, sống trong nước, với mỗi cá thểbao gồm một tế bào duy nhất gồm chất nguyên sinh, tạo thành một nhóm các loài sinh vật nguyên thủy nhất trong thế giới động vật. Chúng rất đa dạng, nhưng nhìn chung có thể chia thành 3 nhóm dựa trên cơ chế di chuyển. Nhóm Mastigophora có một hoặc nhiều đuôi dài, giúp đẩy cơ thể về phía trước. Nhóm Ciliata, có cùng cơ chế vận động như Mastigophora, nhưng nhiều đuôi ngắn hơn. Nhóm Sarcodina, bao gồm trùng amip, trôi nổi hoặc di chuyển trong nước bằng chính cơ thể có lớp bảo vệ bên ngoài của mình

(2) Ngoài hình thức di chuyển, có một số các đặc điểm khác giúp phân biệt 3 nhóm sinh vật đơn bào. Ví dụ, nhóm Ciliata có ít nhất 2 nhân mỗi tế bào, thường một nhân lớn quy định đặc điểm tăng trưởng nhưng phân hủy trong quá trình sinh sản, và một nhân nhỏ hơn có chứa mã di truyền cần thiết để tạo ra nhân lớn.

(3) Sinh vật đơn bào được coi là động vật bởi vì, không giống thực vật có sắc tố mà một số loài sinh vật đơn bào giống y hệt, chúng không sống bằng các hợp chất hữu cơ đơn giản. Tế bào của chúng thể hiện tất cả các đặc điểm chính của tế bào ở động vật bậc cao.

(4) Nhiều loài sinh vật đơn bào tập hợp các cá thể lại với nhau, gọi là các “tập đoàn trùng roi” với mối liên kết chặt chẽ của các bộ phận và phản ứng đồng nhất với kích thích từ bên ngoài. Những nghiên cứu gần đây về hiện tượng này, cùng với những quan sát bằng kính hiển vi cao cấp có lẽ sẽ buộc chúng ta phải định nghĩa lại thế nào là sinh vật đơn bảo, thậm chí phải xem lại định nghĩa cơ bản nhất rằng chúng có thực sự có 1 tế bào hay không. Dù vậy, với các dữ liệu hiện có, các nhà khoa học đã xác định được khoảng 40,000 loại sinh vật đơn bào. Chắc chắn, khi các phương thức quan sát của chúng ta được cải thiện nhờ công nghệ, sẽ có thêm nhiều các mô hình phân loại ưu việt hơn được đưa ra.

14 tháng 6 2018

Đáp án B

Kiến thức: Từ vựng, thành ngữ, từ trái nghĩa

Giải thích: Thành ngữ: over the moon (rất vui, rất phấn khởi)

stressed (a): căng thẳng very sad: rất buồn

very happy: rất vui satisfied (a): hài lòng

over the moon >< very sad

Tạm dịch: Anh ấy rất vui về kết quả thi