Khi làm lạnh một lượng chất lỏng thì khối lượng riêng của lượng chất ấy tăng. Câu giải thích nào sau đây là chính xác nhất? * 4 điểm Vì thể tích chất lỏng giảm còn khối lượng chất lỏng không thay đổi. Vì thể tích chất lỏng giảm. Vì khối lượng chất lỏng tăng. Vì khối lượng chất lỏng tăng còn thể tích chất lỏng không đổi.

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Bài 6: Chia động từ trong ngoặc cho phù hợp. A robot cannot think or (1. do)………….…… things alone. People use a computer (2. control) ………..……… it. Today, robots (3.be)……….……….. rather popular because they are very useful. Robots can help us to save a lot of time at work. A robot can lift heavy things, build houses and (4. make) ……………..….. cars in factories. Robots can do the housework like (5.clean)……………..…….. the floors, making tea or coffee, doing the washing up, washing clothes, etc. In the future, robots will be able to talk to people, (6. guard) ……………….... our houses, look after, our children when we (7.be) ………………..… away. Robs will be able (8. play)…………………. sports and games with us and even (9. drive) ……………. a car when you are drunk or tired. Robots will be able to do many more complicated things and (10.do)………………….. almost everything instead of us. But one thing robots won’t be able to do is to think like humans. Bài 7: Cho dạng đúng của các từ in đậm. 1. Today robots can help humans to do___________________ work. DANGER 2. Some ___________________ say that tiny robots can swim in the bloodstream and attack diseases in the near future. SCIENCE 3. Most children are excited by the ________________________ of robots. DEVELOP 4. Robots don’t have _________________________ to think about their action before acting. ABLE 5. The robots transmit _____________________ to me and I can ask them to perform some functions. INFORM 6. Many people are interested inattending the _________________ robot show between 15 countries in the world. NATION Bài 8: Viết lại các câu sau sao cho nghĩa không đổi. 1. My sister is interested in watching TV My sister likes…………………………………….………………………..…….. 2. The Nile is the longest river in the world. No river……………………………………..……………………………………. 3. We will probably go to the moon for our summer holiday in 2050. We might…………………………………………………..……………………... 4. In the future, home robots can do all our homework. In the future, home robots will…………….……………….…………………….. 5. Jimmy regrets not being able to play tennis well. Jimmy wishes he could…………….………………………………………….…. 6. Mr. Phong has to wear his glasses to read the newspaper. Mr. Phong can not…………….………………………………………………..… 7. The robot in my house can clean the floors very well. The robot in my house is very good …………………………….………………. Bài 9: Sử dụng các từ gợi ý để hoàn thành các câu sau. 1.I/ agree/ the idea/ that robots/ be/ powerful/ future./ ________________________________________________________________ 2.Firstly,/ robots/ can/ do/ same work/ for/ 24 /hour/ without tiredness. ________________________________________________________________ 3.Secondly,/ robots/ become/ very smart/ and do/ more complicated things/ like/ fly a plane/ and/ play sports. ________________________________________________________________ 4.Finally,/ they/ can/ do/ some/ job/ better/ humans. ________________________________________________________________ 5.For/ above reasons,/ I/ believe/ that robots/ become/ very powerful/ and we must/be/careful. ________________________________________________________________