Cau 1. Khi viết thêm số 24 vào bên trái một số tự nhiên có hai chữ số ta được số mới gấp 31 lần số đã cho. Tìm số đó.

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Choose the best answer to complete each of the following sentences.(Ghirõ phần giải thích khi làm bài) Ex: 1. C (fasten the seatbelt: thắt dây an toàn) 1. Drivers have to__________ their seatbelt whenever they drive. A. put B. tie C. fasten D. put on 2. We should wait for the traffic lights__________ before we cross the street. A. turn green B. to turn green C.turn yellow D. to turn yellow 3. All of us have to obey__________ strictly. A. traffic rules B. traffic C. traffic jam D. regular 4. Cyclists and motorists have to wear a__________ when they ride a motorbike. A. hard hat B. cap C. mask D. helmet 5. He forgot to give a__________ before he turned left and got a ticket. A. signal B. sign C. light D. hand 6. __________does it take you to get to Ho Chi Minh City by plane? - About 2 hours. A. How far B.How much C. How long D. How many 7. There__________ a bus station in the city centre, but it has been moved to the suburbs. A. used to be B. used to have C. use to have D. were 8. I__________ marbles when I was young, but now I didn’t. A.play B. used to play C. have played D. didn’t use to play 9. “__________ is it from your house to the nearest bus stop?” - “About 50 meters’ A. How far B. How long C.How often D. How much 10. We should__________ the street at the zebra crossing. A. walk B. walk on C. walk through D. walk across 11. John used to go to school __________. A. with bicycle B. by foot C. in car D. by bus 12. Public __________ in my town is good and cheap. A. transport B. tour C. journey D. travel 13. _______ is not very far from here to the city center. A. That B.This C.It D. There 14. When there is a traffic jam, it__________ me a very long time to go home. A. costs B. takes C. lasts D. spends 15. Mai’s dad usually drives her to school__________ her school is very far from her house. A. but B. though C. because D. or 16. Yesterday Hoa and Lan__________ round West Lake. It took them an hour. A. cycle B. cycles C. cycling D. cycled 17. Minh used to__________ his homework late in the evening. A. does B. do C. doing D. did 18. If people __________ the rules, there are no more accidents. A. follow B. take care of C. obey D. remember 19. You should__________ right and left when you go across the roads. A. see B. look C. be D. take 20. Hurry up or we can’t__________ the last bus home. A. keep B. follow C. go D. catch 21. There used to be fewer people and __________ on the roads. A. roofs B. helmets C. helicopters D. vehicles 22. Do you know the __________ in the UK is to keep to the left? A. traffic light B. traffic rule C. traffic jam D. speed limit 23. It is dangerous to ride a motorbike without a __________ A. helmet B. triangle C. tricycle D. circle 24. In Hanoi, during rush hour, some road users ride their motorbikes on the __________ A. driving licence B. lane C. pavement D. seat belt 25. Traffic is terrible during the __________ when everyone is in a hurry to get to work or come back home. A. traffic light B. road sign C. traffic rule D. rush hour