Một ca nô xuôi dòng từ A đến B rồi lại ngược dòng từ B về A với vận tốc bằng 45km/giờ. Tính quãng đường AB biết vận tốc dòng nước bằng 5km/giờ và thời gian ngược dòng nhiều hơn thời gian xuôi dòng là 24 phút.

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Lm bài này + thêm nghĩa của câu I. Change the following sentences into the passive voice. 1. They grow rice in tropical countries.→ ______________________________________________ 2. Mr. Green loves his children very much.→ _____________________________________________ 3. People don’t speak French here.→ __________________________________________ 4. Someone broke his windows last night.→ _________________________________ 5. The police didn’t find the lost boy yesterday.→ ___________________________________ 6. About thirty million people are watching this live show now.→ _________________________________ 7. Do they teach French in our school?.→ _________________________ 8. Jack has typed the article recently.→________________________________________ 9. The police haven’t found the murderer yet.→ _______________________________________________ 10. They were planting trees in the garden.→ _______________________________ 11. They had wrapped the package carefully before they posted it.→ _________________________ 12. Children should treat old men with respect.→ __________________________________________ 13. The computer can do all the accounts. → ____________________________________ 14. They are going to build a new school.→ ______________________________________ 15. He isn’t going to buy that house.→ ____________________________________ 16. They will pull down that building→ ________________________________________ 17. The teacher won’t correct the exercises tomorrow.→ _________________________________ 18. You have to keep dangerous chemicals in the safe place.→ ____________________________________ 19. Police had to break the meeting up.______________________________________ 20. They may use that room for the classroom.→ _______________________________________________ 21. You must wash your hands. → _______________________________________________________________________ 22. They ought to knock down the old building. → _______________________________________________________________________ 23. You should type that report today. → ________________________________________________________________________ 24. Nobody has used this room for ages. → ________________________________________________________________________ 25. No one can solve that problem. → ________________________________________________________________________ 26. No one told us the news. → ________________________________________________________________________ 27. Paul didn’t tell me the ending of the story. → ________________________________________________________________________ 28. The teacher will give her a prize if she works well. → ________________________________________________________________________ 29. Her mother bought her a doll last week. → ________________________________________________________________________ 30. The police found the robber in the forest yesterday. → ________________________________________________________________________

II. Read the passage carefully. MY VILLAGE I live in a village by Mekong River. Every day, like most of my friends, I walk to school. It is three kilometers away. After class, I often help my mother to collect water from the river and feed the chickens. At the weekend, the villagers often gather at the community hall where there is a TV. The adults watch TV, but more often they talk about their farm work and exchange news. The children run around playing games and shouting merrily. Laughter is heard everywhere. My father sometimes takes me to the market town nearby where he sells our home products like vegetables, fruits, eggs... He then buys me an ice cream and lets me take a ride on the electric train in the town square. I love those trips. On starry nights, we children lie on the grass, looking at the sky and daring each other to find the Milky Way. We dream of faraway places. Answer the following questions. 1. Does the boy like riding on the electric train in the town square? 2. What do the children do on starry nights? 3. Do you like to live in the countryside or in the city? Why? III. Supply suitable words to complete the following passage. Our classes take place for three hours every morning (1) Monday to Friday.The maximum class size (2) twenty and the average is ten. We use modernmethods of (3) and learning, and the school has a language laboratory, a videocamera and recorder. You will only be successful (4) improving your English,however, if you work hard and (5) speaking English as much as you can. Youwill take a short (6) in English as soon as you arrive. In this way, wecan put you in a (7) at the most suitable level. There are two classes (8) the elementary level; one is for complete beginnersand the (9) is for students who know a (10) English. In both classes,you will practise simple conversations