Đốt cháy 3g chất hữu cơ A, thu đc 8,8 g khí CO2 và 5,4 g H2O a) Trong chất A có những nguyên tố nào ? b) Biết phân tử khối của A<40. tìm CTPT của A c) Chất A có làm mất màu dd Brom không d) Viết PTHH của A vs clo khi có ánh sáng

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Bài tập  Thì hiện tại hoàn thành Chia động từ ở thì hiện tại hoàn thành 1. There is no more cheese. I (eat)……………. it all, I’m afraid. 2. The bill isn’t right. They (make)………….. a mistake. 3. Don’t you want to see this programme? It ………….(start). 4. It’ll soon get warm in here. I (turn)……….. the heating on. 5. ………They (pay)…….. money for your mother? 6. Someone (take)………………. my bicycle. 7. Wait for few minutes, please! I (finish)……………. my dinner. 8. ………You ever (eat)………….. Sushi? 9. She (not/come)…………… here for a long time. 10. I (work…………..) here for three years. 11. ………… You ever …………..(be) to New York? 12. You (not/do) ………….your project yet, I suppose. 13. I just (see)………. Andrew and he says he ……..already (do)………. about half of the plan. 14. I ………..just (decide)……… to start working next week. 15. He (be)…………. at his computer for seven hours. 16. She (not/have) ……………any fun a long time. 17. My father (not/ play)……….. any sport since last year. 18. I’d better have a shower. I (not/have)………. one since Thursday. 19. I don’t live with my family now and we (not/see)…………. each other for five years. 20. I…… just (realize)…………... that there are only four weeks to the end of term. II. Chia động từ 1. He often (go)................. toschool on foot. 2. It (rain) .................very hard now. 3. The sun (warm).................... the air and (give) .....................us light. 4. Look! A man (run).................................... after the train. 5. She (go)........................... to school everyday. 6. Bad students never (work)........................... hard. 7. It often (rain) in the summer. It (rain) ..........................now. 8. The teacher always (point) ......................... at the black-board when he (want)......................... to explain something. 9. Mother (cook) ......................... some food in the kitchen at the moment, she always (cook) ......................... in the morning. 10. I always (meet) ......................... him on the corner of this street. 11. Where you (go) ......................... now?- I (go) ......................... to the theater. 12. He (not do.........................) morning exersices regularly. 13. He (do) .........................morning exersices now? 14. Wather (boil) ......................... at 100 defrees centigrade. 15. He (meet) .........................the dentist next week. 16..........................you (be) ......................... a food student? 17. They usually (not go) ......................... to school by motorbike. 18. He (swim) .........................overthere now. 19. She (come) ......................... here next month. 20. They (not be) ......................... doctors. 21. He often (get) ......................... up late. 22..........................you often (watch) ......................... TV? 23. Mr.Brown (listen) ......................... to music now? 24. I usually (go) (shop) .........................on the weekend. 25. Hai often (wash) ......................... his face at 6.15. 26. She (play) ......................... badminton at the moment? 27. Thanh and Mai always (see) ......................... a movie on Saturday. 28. He often (take) .........................a bus to school? 29. We (be) ......................... students in class 8A. 30. She often (not do) ......................... homework in the evenin

I. Choose the best option to complete each sentence. Circle A or B. 1. We ______ keep our school clean. A. must B. mustn’t 2. You ______ talk loudly in class. A. must B. mustn’t 3. You ______ litter in public places. A. must B. mustn’t 4. You ______ travel alone because it’s dangerous. A. must B. mustn’t 5. We ______ camp here because it’s near a school. A. must B. mustn’t II. Read the passage and answer the questions. Watching television is an interesting and fun activity. The first television broadcast in Australia was in 1956. Back then, the pictures on a TV were black and white only. Television has changed a lot since then. There are several channels and they show different TV programmes. In Western Australia, the main channels are ABC, Seven, Nine, Ten, and SBS. TV guides tell us what programmes are showing on which channel, and at what time on a day. Many programmes on television are episodes. They are part of a series. These episodes usually last for either 30 minutes or a full hour. At the weekend there are interesting films. You can watch them instead of going to the cinema. 1. When was the first Australian TV broadcast? ______________________________________ 2. How were the pictures on a TV then? ______________________________________ 3. List any three TV channels in Western Australia. ______________________________________ 4. Where can you find out the time of your favourite TV show? ______________________________________ 5. How long do episodes on TV usually last for? ______________________________________