1.Chọn phát biểu sai : A.Các chất được cấu tạo từ các hạt nhỏ riêng biệt gọi là các nguyên tử , phân tử B.Nguyên tử là hạt chất nhỏ nhất C.Phân tử là một nhóm các nguyên tử kết hợp lại D.Giữa các nguyên tử , phân tử không có khoảng cách. 2.Tại sao các chất trông đều có vẻ liền như một khối mặc dù chúng đều được cấu tạo từ các hạt riêng biệt? Câu giải thích nào sau đây là đúng nhất? A.Vì các hạt vật chất rất nhỏ, khoảng cách giữa chúng cũng rất nhỏ nên mắt thường ta không thể phân biệt được. B.Vì một vật chỉ được cấu tạo từ một số ít các hạt mà thôi. C.Vì kích thước các hạt không nhỏ lắm nhưng chúng lại nằm rất sát nhau D.Một cách giải thích khác.

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6. Give the correct form of the verbs. 1. The bill isn’t right. They (make)………….. a mistake. 2. Don’t you want to see this programme? It …………. (start). 3. I (turn)……….. the heating on. It’ll soon get warm in here. 4. ……..they (pay)…….. money for your mother yet? 5. Someone (take)………………. my bicycle. 6. Wait for few minutes, please! I (finish)……………. my dinner. 7. ………you ever (eat)………….. Sushi? 8. She (not/come)…………… here for a long time. 9. I (work)………….. here for three years. 10. ………… you ever …………..(be) in New York? 11. You (not/do) ………….yor project yet, I suppose. 12. I (just/ see)………. Andrew and he says he ……..already (do)………. about half of the plan. 13. I ………..just (decide)……… to start working next week. 14. He (be)…………. at his computer for seven hours. 15. She (not/have) ……………any fun a long time. 16. My father (not/ play)……….. any sport since last year. 17. I’d better have a shower. I (not/have)………. one since Thursday. 18. I don’t live with my family now and we (not/see)…………. each other for five years. 19. I…… just (realize)…………… that there are only four weeks to the end of term. 20. The train drivers (go)……… on strike and they stopped working at twelve o’clock. 21. How long…….. (you/know)………. each other? 22. ……….(You/ take)………… many photographs? 23. (She/ eat)………………. at the Royal Hotel yet? 24. He (live) ………….here all his life.. 25. Is this the second time he (lose)……………. his job? 26. How many bottles………… the milkman (leave) ………….? He (leave) ……….. six. 27. I (buy)…………. a new carpet. Come and look at it. 28. She (write)………….. three poems about her fatherland. 29. We (finish) ……………………three English courses. 30. School (not, start)……………..yet. 7. Rewrite sentences without changing the meaning 1.She has never drunk whisky before. ………………………………………………………………………… 2.He has never known me before. ………………………………………………………………………… 3.This is the first time we’ve visited Ha Long Bay. …………………………………………………………………………. 4.The last time she kissed me was 5 months ago. …………………………………………………………………………. 5.I last had my hair cut when I left her. …………………………………………………………………………. 6.It is a long time since we last met. …………………………………………………………………………. 8. Put the verbs into the correct tense (simple past or present perfect simple). 1. A: (you / play / already) the new computer game? 2. B: No, not yet. I only (buy) it yesterday and I (have / not) the time yet. 3. A: (you / go) to the cinema last night? 4. B: Yes. I (be) there with Sue and Louis. (you / be) to the cinema recently? 5. A: I last (go) to the cinema two weeks ago. 6. B: So you (see / not) the new action film yet. 7. A: No, unfortunately not. (you / enjoy) it? 8. B: Oh, I really (love) it. But Sue (like / not) it – too much action! 10. A: But why (you / take) her with you? She (tell) me last week that she (hate) action films. 11. B: I think she has an eye on Louis. She (try) to flirt with him all the time. So he (can / concentrate / not) on the film. 9. Put the verbs into the correct tense (simple past or present perfect simple). 1. I (just / finish) ..................................................... my homework. 2. Mary (already / write) ........................................ five letters. 3. Tom (move)................................................. to this town in 1994. 4. My friend (be) ........................................................ in Canada two years ago. 5. I (not / be) ......................................................to Canada so far. 6. But I (already / travel)........................................ to London a couple of times. 7. Last week, Mary and Paul (go) .............................................. to the cinema. 8. I can’t take any pictures because I (not / buy)..................................... a new film yet. 9. (they / spend).................................. their holiday in New Zealand last summer? 10. (you / ever / see) ................................................... a whale?