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hoan9bdongtho
2 năm trước
cho đường tròn (o) ,diểm A nằm ngoài đường tròn , từ A vẽ tiếp tuyến AB, AC (B,C là tiếp điểm).gọi H là giao điểm của AO và BC a, CM : OA vuông góc vs BC tai H B. cm : AE.AD=AH .AC
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II/ EXERCISES A. Complete the sentences below, using the correct form or tense of the verbs in brackets 1. I enjoy (fish ) …………………because it (be) ………………. relaxing . 2. My uncle likes (live) ……………………. in the countryside . I think he (move) ………………….. to his hometown next year . 3. What ………. your sister often ( do) ……………… in her free time ? She loves (read)…………………… . 4. They (live) …………….. in Ho Chi Minh City for ten years . Now they (live) …………………….. in Ha Noi 5. He (go) ………………. to the bookstore yesterday and (buy) ……………….. some interesting books. 6. …………..you (finish) …………… your homework yet ? Yes, I (finish) …………… it ten minutes ago . 7. Her brother (work) ………………… in that company since he (graduate) from the University. 8. She always (get) …………… up early every day but she (get) ………. up late yesterday morning. 9. It (not rain) …………………….. in the dry season . 10. Don’t worry . I (go) ……………… swimming with you tomorrow. B. Complete the second sentence so that it has a similar meaning to the first . 1. My sister has played the piano for five years . My sister started ……………………………………………. 2. I think cooking is interesting . I find …………………………………………….. 3. She couldn’t go to school because of the bad weather . Because ………………………………………………………………... 4. They started to learn English three years ago . They have ………………………………………………………… 5.Mr Nam intends to buy a new house in Nha Trang next week . Mr Nam ………………………………………………………. C.Underline and correct a mistake in each sentence below . 1. His father finds ice –skate difficult. ………………… 2. Why do you want to donate blood ? Because I am scared ……………………. 3. Lan enjoys to dance because she thinks dancing is interesting. ……………… 4. Mrs Nga has written that report since four days . …………………………. 5. We will to help the newcomers . ………………………… D.Match A and B to make meaningful sentences A B 1. Eat a lot of red fruits and vegetables A. because it helps to make you fitter and more active . 2.Stay outdoors more and do more physical activities. B. because they provide vitamin A which is good for your eyes . 3. Use eye -drops when you sit up late or when you return from a dusty area . C.or you will become weak and tired . 4. Don’t read or study when there is not enough light . D. to prevent your eyes from getting dry . 5. Eat enough calories . E . because it is harmful for your eyes . 1. …………….., 2………………..,3….…….,4….……….,5…………… E. Write full sentences using the suggested words and phrases given 1. My aunt/ uncle/ always/ give/ me / dolls/ special occasions . ………………………………………………………………………………………… 2. Hoa/ love / drawing / but she / say/ not continue/ hobby / the future . ………………………………………………………………………………………… 3. I hope/ the future/ my father/ teach me / how/ do eggshell carving . ………………………………………………………………………………………… 4. It/ be/ good idea/ eat/ different/ kinds / fruit/ vegetables / every day . ………………………………………………………………………………………… 5. Eat / fresh fruit/ be/ much better/ you / than / glass/ fruit juice. ……………………………………………………………………………………….. F. Choose the right words to complete the sentences. Homeless people, Stomachache, volunteer, temperature , sore throat, sunburn, arranging flowers , dancing, making pottery, community service 1. The activities that individuals or organizations do to benefit a community are called…………………………….. 2. You are a ………………………….. if you help other people willingly and without payment. 3. She looks very red. She was outdoors all day yesterday . I think she has ………………. 4. He ate some sea food . Now he feels sick . He says he has a ………………… 5. He was holding his neck . I think he has a …………………… 6. She looks so tired. She can’t keep her eyes open . She is very hot too. She has a ………………… . 7. My sister always buys flowers and puts them in a vase to display in the house . her hobby is …………………….. 8. If you spend most of your time making vases of bowls from clay. Your hobby is …………………………………. 9. His brother dances very well . His hobby is ……………………. 10. ……………………. are those who do not have a home and really need help. G. Complete the sentences with MORE / LESS 1. Eat ……………. Junk food . It makes you fat . 2. Wash your hands ……………… you will have less chance of catching flu . 3. Sleep …………….. but try to wake up at the usual time . Even at weekends. 4. Go outside …………….. if you need to go outside ,wear a sunhat . 5. Watch ……………. TV . Looking at the screen for too long hurts your eyes . làm ơn giúp mình

From: Julie@tmail.com To: Chloe@teenmail.com Subject: An unusual home!! Hi Chloe, I have to write to you about this! In Pennsylvania, there is a very unusual home. It is a house in the shape of a shoe. Yes, a shoe! The shoe house has got a ground floor. Above that there are four more storeys. It has three bedrooms and two bathrooms. There is also a kitchen and a living room. Outside, there is a beautiful garden with many trees and plants. The house is made of wood and metal. It isn’t a home any more. You can buy ice-cream there now. You should see it. It is very strange, but I like it. Bye! Julie 1. Where is the house? ____ 2. What shape is it? ____ 3. How many floors are there? ____ 4. How many rooms has it got? ____ 5. What is there outside the house? ____ 6. What is the house made of? ____ 7. Is it a home now? ____ 8. What can you do there now?

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