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nguyenthichungvietan123
2 năm trước
Cho tam giác ABC nhọn, đường cao AH. Gọi E,F lần lượt là trung điểm của AB và AC. a) Cho BC = 6cm, tính EF. b) Qua B kẻ đường thẳng vuông góc với BC tại B, cắt HE tại I. Tứ giác AHBI là hình gì ? Vì sao? c) Kẻ IK vuông góc với HF tại K. Chứng minh góc AKB = 90 độ.
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1. Fill in each blank with a suitable preposition 1. The students are reading books ... the library . 2. I usually buy a phone carb ... the post office . 3. The New World hotel is Le Loi street . 4. There are two pictures ... the wall . 5. Minh lives ... a beautiful house ... the city . 6. It takes 20 mins ... my house ... school . 7. The post office is ... the movie theater . 8. I will be ... home all day . 9. The bus stop ... the right of my school . 10. The drugstore ... the left . 11. It takes a day from here to Hanoi ... coach . 12. It's very hot . Let's go ... a swim . 13. My father often goes abroad ... business. 14. I'm sorry , but i'm very busy ... my homework now . 15. It's very nice today . Why don't we go ... a walk ? 16. Your school bag is different ... mine . 2. Use the correct form of 1. Your test is (good) than mine . 2. Her hair is (short) of all. 3. Elephant is (heavy) animal in the world . 4. He arrives (early) than we thought . 5. This is (high) building in the city . 6. This crarf is (expensive) in the shop . 7. This coffee is very weak . I like a bit (strong) 8. The trip is (long) than we thought . 9. Your questions are (complicated) mine . 10. Coffee isn't (good) as orange juice . 11. Health and happiness are (important) money . 12. What is (interesting) program on TV ? 13. Plane is (fast) transportation . 14. Is this room (comfortable) that one . 15. She has (many) friends than me . 16. Which of these two books is (interesting) ? 17. He drinks (little) beer of three men . 18. The country isn't (crowd) the city. GIÚP MÌNH VỚI , MÌNH CẦN GẤP !!!!

C/ PRECTISE: I. Put the verbs into correct form: past progressive or past simple. 1. The doorbell ........................ (ring) while Tom ....................... (watch) television. 2. How fast .................. you ......................... (drive) when the accident ............... (happen) ? 3. Anna and Susan ............... (make) dinner when Martin ....................... (arrive) home. 4. The light ..................... (go) out while we ................. (have) dinner. But it .............. (come) on again after about ten minutes. 5. "What ..................... you ........... (do) this time yesterday?" - I ........... (work) on the computer." 6. It suddenly ............ (begin) to rain while Laura ............ (sit) in the garden. 7. It .............. (be) cold when we ............... (leave) the house that day, and a light snow ......... (fall). 8. When I last .......... (see) them, they ............... (try) to find a new house near their work. 9. I .................. (walk) along the street when I suddenly ........... (feel) some thing hit me in the back. I ............... (not/ know) what is was. 10. When we ............. (deive) down the hill, a strange object ............. (appear) in the sky. II. Write sentences whit the cue words, using the past progressive tense. Ex: I/ weite/ my report/ 8 o'clock last night -> I was writing my report at 8 o'clock last night 1. They/ play tennis/ 10.30 yesterday morning. => .............................................................................................. 2. Ann/ do/ homework/ 5 o'clock this afternoon. => ............................................................................................ 3. My father/ wash/ car/ from five to six. => ......................................................................................................... 4. This time las year/ we/ live/ France. => .............................................................................................................. 5. The students/ offer/ flowers/ the visitors. => .................................................................................................... 6. I/ cook/ dinner/ half an hour ago. => ................................................................................................................. 7. She/ work/ the studio/ that time. => .................................................................................................................. 8. What/ you/ do/ from 3 to 6 yesterday afternoon?. => ..................................................................................... III/ Choose the best answer 1. Alice " saw/ was seeing " the accident when she was catching the bus. 2 What " were you doing/ did you do " when I called ? 3. I " didn't visit / weren't visiting " my friends last summer holiday. 4. It " rained/ was raining " heavily last July. 5. While people were talking to each other, he " read/ was reading " his book. 6. My sister " was eating/ ate " hamburgers every weekend las month. 7. While we " were running/ ean " in the park, Mary fell over. 8. " Did you find/ Were you finding " your keys yesterday? 9. Who " was she dancing/ did she dence " with at the party last night? 10. They " were watching/ watched " football on TV at 7.pm. yesterday.

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