trên cùng một nữa mặt phẳng bờ chứa tia ox vẽ tia oy,oz sao cho xoy=50,xoz=120 a) tính yoz b) vẽ tia on ,om lần lượt là tia phân giác của xoy,yoz. Tính nom c) vẽ tia ot là tia đối của oz . Tia ox có phải là tia phân giác của yot không , vì sao

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Ex1:Choose the best answer. 1. He books for poor children for years A. has collected B. collects C. is collecting D. collected 2. Ngoc loves outdoors with trees and flowers. A. is B. be C. being D. was 3. _______ your homework yet? A. Are you doing B. Have you done C. Do you do D. Did you do 4. She _________________ this film already. A. am seeing B. have seen C. saw D. has seen 5. Nam Cao _______________ a lot of novels. A. has written B. writes C. wrote D. writing 6. Her mother _____________ three books. She is going to start the fourth one soon. A. has written B. writes C. wrote D. written 7. I think I ____________ him before. A. meet B. met C. have met D. meeting 8. Oh, yes! Now I remember. I ____________ him when I was in Hoi An. He was our guide! A. meet B. met C. have met D. will meet 9. I blood twice, and presents to sick children in the hospital recently. A. donate - give B. donated - gave C. have donated - have given D. have donated – gave 10.She blood twenty times so far. A. donates B. has donated C. is donating D. to donate 11.Let’s help the street children because they have bad . A. live B. living conditions C. ways of life D. earnings 12.They have decided to ride to work it is good for their health and the environment. A. so B. but C. although D. because 13. I’ve ________ seen this film. Let’s watch something else. A. never B. ever C. already D. yet 14. We can help to reduce ________ by using public transportation, biking and walking. A. air pollution B. water pollution C. social problems D. community service 15._______ do you do volunteer work? - Every weekend. A. How long B. How far C. How much D. How often Ex 2 : Choose the correct word A, B or C for each gap to complete the following passage. (1) January 17th, 1995, a powerful earthquake hit the city of Kobe, Japan. Many buildings (2) or collapsed. Soon after the earthquake, people in Kobe (3) working together to save their city. Neighbours pulled each other out (4) collapsed buildings. Ordinary people (5) out fires even before the fire trucks arrived. Volunteers in Kobe organized themselves into (6) . They worked out a system to send (7) to people who needed. Other teams searched for belongings in damaged stores and homes. Some people (8) food, water, clothes, and electric generators to different part of the city. Some volunteers took (9) of children who had lost their parents. Teams of volunteers from outside Japan helped, too. Today, Kobe has been built. But people there still remember the outpouring of support they (10) from all over the world back in 1995. 1. A. in B. at C. on D. from 2. A. is burning B. burned C. burning D. burn 3. A. to begin B. are beginning C. begin D. began 4. A. into B. of C. on D. with 5. A. to put B. putting C. puts D. put 6. A. teams B. pair C. group D. friends 7. A. helped B. helping C. help D. to help 8. A. brought B. bringing C. brings D. brought 9. A. part B. care C. caring D. note 10.A. received B. is receiving C. have received D. receiving