Bài 1. Cho tam giác ABC cân tại A. Trên tia đối của tia BC và CB lấy theo thứ tự điểm D và E sao cho BD = CE. a) CMR: tam giác ADE cân b) Gọi M là trung điểm của BC. CMR: AM là tia phân giác của và c) Từ B và C kẻ BH, CK theo thứ tự vuông góc với AD và AE. CMR: BH = CK. d) CMR: HK // BC. e) Cho HB cắt CK ở N. CMR: A, M, N thẳng hàng. Bài 2. Cho tam giác ABC cân tại A (), lấy M . Từ M kẻ MH // AB (H), kẻ MI // AC (I ). a) CMR: . b) CMR: AI = HC. c) Lấy N sao cho HI là trung trực của MN. CMR: IN = IB. Bài 3. Cho tam giác ABC vuông tại A, AB > AC. M là trung điểm của BC. Trên tia đối của tia MA lấy điểm D sao cho MD = MA. a) CMR: AB = DC và AB // DC. b) CMR: ABC = CDA c) Trên tia đối của tia AC lấy điểm E soa cho AE = AC. CMR: BE // AM.

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I/ Use a phrase or clause of purpose into combine each pair of sentences below: 1. The boys stood on the benches. They wanted to get a better view. => The boys stood on the benches to/ in order to/ so as to get a better view. => The boys stood on the benches so that/ in order that they could get a better view. 2. We lower the volume of the radio. We do not want to bother our neighbors. __________________________________________________________________________ 3. I will write to you . I want you to know my decision soon. __________________________________________________________________________ 4. These men were whispering. They did not want anyone to hear their conversations. __________________________________________________________________________ 5. The boy feigned to be sick. He hoped we did not make him in work. __________________________________________________________________________ 6. The man spoke loudly. He wanted anybody to hear him clearly. __________________________________________________________________________ 7. Doris often goes home as soon as the class is over. She does not want her mother to wait for her. __________________________________________________________________________ 8. John gets up early. He does not want to be late for class. __________________________________________________________________________ 9. Mary hid the novel under her pillow. She did not want her father to see it. __________________________________________________________________________ 10. Alice prepares her lesson carefully. She wants to get high marks in class. __________________________________________________________________________ II/ Rewrite the following sentences , using PHRASES of purpose. 1. Leave early so that you may get home before dark. =>Leave early to get home before dark. 2. This man changed his address constantly so that he could avoid the police. => _____________________________________________________________________ 3. I shouted in order that I could warn everyone of danger. => _____________________________________________________________________ 4. Banks are developed so that they can keep people’s money safe. => _____________________________________________________________________ 5. Mary went to the library in order that she could borrow some books. => _____________________________________________________________________ 6. Yesterday father went to the bank so that he would open a checking account. => _____________________________________________________________________ 7. I went to see him so that I could find out what had happened. =>; _____________________________________________________________________ 8. Tom is saving up so that he can buy a new bicycle. =>; _____________________________________________________________________ 9. He hurried so that he could catch the train. => _____________________________________________________________________ 10. She is learning French so that she will be able to speak it when she comes to Paris. =>_____________________________________________________________________ III/ Change the phrases of purpose to clauses of purpose or vice versa: 1. We hurried to school so as not to be late. =>we hurried to school so that/ in order that we couldn’t be late. 2. You should get up early so that you will have time to review your lesson. => You should get up early to/ so as to/ in order to review your lesson. 3. Some young people like to earn their own living in order that they will be independent of their parents. =>; _____________________________________________________________________ 4. He climbed the tree in order to get a better view. => _____________________________________________________________________ 5. We should do morning exercises regularly so as to improve our health. He climbed the tree in order to get a better view. => _____________________________________________________________________ 6. We should take advantage of the scientific achievements of the world so that we can develop our national economy. =>_____________________________________________________________________ 7. Everyone in the world must unite their efforts to maintain and protect peace. =>; _____________________________________________________________________ 8. She put on warm clothes so that she would not catch cold. =>; _____________________________________________________________________ 9. He hurried to the station so as not to miss the train. =>_____________________________________________________________________ 10. He climbed the tree in order to get a better view. =>; _____________________________________________________________________