Bài 3: Cho tam giác ABC cân tại A. Lấy I là trung điểm BC. Trên tia đối của CB lấy điểm N, trên tia đối của BC lấy điểm M sao cho CN=BM. a) Chứng minh: AI là tia phân giác góc BAC; b) Chứng minh AM=AN; c) Qua B vẽ đường thẳng vuông góc với AB cắt tia AI tại K. Chứng minh KC vuông góc AC.

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3. Choose the correct option for each gap in the sentences 1. Minh used to _____ his homework late in the evening. A. does B. do C. doing D. did 2. If people _________ the rules, there are no more accidents. A. follow B. take care of C. obey D. remember 3. You should _________ right and left when you go across the roads. A. see B. look C. be D. take 4. Hurry up or we can't _________ the last bus home. A. keep B. follow C. go D. catch 5. Lan used to go to school _________. A. with bicycle B. by foot C. in car D. by bus 6. Public _________ in my town is good and cheap. A. transport B. tour C. journey D. travel 7. _________ is not very far from here to the city center. A. That B. This C. It D. There 8. When there is a traffic jam, it _________ me a very long time to go home. A. costs B. takes C. lasts D. spends 9. Mai's dad usually drives her to school _________ her school is very far from her house. A. but B. though C. because D. or 10. Yesterday Hoa and Lan _________ round West Lake. It took them an hour. A. cycle B. cycles C. cycling D. cycled 4. Fill each blank with a word in the box vehicles across did ride feels break it rules accidents after 1. What _________ you do last Sunday? 2. I stayed at home and looked _________ my younger brother yesterday. 3. Does your bike ever _________ down on the way to school? 4. We must always obey traffic _________ for our safety. 5. How far is _________ from your house to the bus stop? 6. He used to _________ a tricycle when he was three years old. 7. Now there are more traffic _________ than there used to be in this city.