Cho tam giác ABC nhọn(AB<AC) nội tiếp (O). Gọi H là giao của 3 đường cao AD, BE, CF của TAMgiac ABC a) Chứng minh: BDHF và BCEF là các tứ giác nội tiếp. b) Chứng minh: FH là phân giác của góc EFD

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1.It (not rain) .... ...................... in the dry season. 2.Lan (take) ........................... her younger brother to the zoo last Sunday. 3.Children are interested in (watch).............cartoons. 4.Teenagers are fond of.................................(wear) jeans. 5.They (give)............................. me the letter a few minutes ago. 6. You (do) ...........the housework, won't you? 7. We (learn) ......... ........................ English for 7 years. 8.(you/have) .................... breakfast yet? 9. My little sister (drink) ............ ..........milk every day. 10.The doctor sometimes (return) .................................home late. 11. They (not/ do)............ .............. homework yet. 12.(you/finish)...................................... your writing vet2 13. He think that it (rain).......... tonight 14. I am excited about (travel). ......................to Nha Trang next week. 15. They keep (talk) ........ ............. about an old friend they met yesterday. 16. It is usually easier ...................... (learn) a subject by... (read) books than by .......... (listen to lectures. 17. Nam (cook)................. .........dinner tonight, won't he? 18.They've finished (do) ...................................their homework. 19. Would you mind (help)......... ................. me with this work? 20. We decided (rent)..............a house with a swimming pool. 21. Let me (pay)....... for the meal. You paid last time. 22. He promises that he (pass)..........the exam. 23. Jimmy wishes he (be).................... old enough to drive a car. 24. They decided (go)..............................out for dinner. 25. (you/ever/ be)..................................to Tokyo? 26. Could you show me how (get)......................................to the station? 27. You (go) .............................to the party tonight, will you? 28. His uncle (teach) ........ .............. English in our school five years ago. 29. They (not go) ................... to the movies last Sunday. 30. They (build) ........... ....... a new school in this area next year. 31. My brother (work) ............... ............ in this factory for many years. 32.They won't come to the party,... ..............they?