Rút gọn biểu thức :
\(\frac{1}{\sqrt{x-1}-\sqrt{x}}+\frac{1}{\sqrt{x-1}+\sqrt{x}}+\frac{\sqrt{x^3}-x}{\sqrt{x}-1}\)

Rewrite the following sentence by using Because + clause, Because + N/ cụm N :
1. He is bad at English because he is very lazy.
2. He didn't come to class because of his illness.
3. Everyone likes and admires her because of her intelligence.
4. The flight 202 was delayed because the weather was bad.
5. I didn't come on time because it rained heavily.
6. They can't miss the meeting because of its importance.
7. I was late for the meeting because the traffic was heavy.
8. My grandmother can't work hard because of her age.

Rewrite the following sentences but keep the meaning :
1. Although she performed well, she didn't receive good comments from critics.
=> Despite her ....................
2. I'm frightened by horror films: however, I enjoyed wathching them.
=> In spite ....................
3. It was noisy. The children slept well.
=> Despite ..............
4. The film poster is fascinating. I don't want to see this film.
=> In spite of ................
5. Although our plan is careful, we made some mistakes.
=> Despite ....................
6. Although he had a good salary he was unhappy in his job.
=> In spite of ...................
7. In spite of the forecast it stayed fine.
=> Although the rain was ....................
8. Although his leg was broken, he managed to get our of the car.
=> In spite of .................
9. Although the team played well, they lost.
=> In spite of ....................
10. The flat's so noisy but we enjoy living there.
=> Even .....................

Write questions for the underlined parts or beginning with the words :
1. I spent much time on reading books.
=> .................
2. It took 2 days for them to go to Ca Mau. (how long)
=> ....................
3. His mother looks very beautiful. (how)
=> ....................
4. The train to Hai Phong will leave at 7 o'clock.
=> ....................
5. My father is an engineer of Song Da construction Corporation. (what)
=> ..................

Write the second sentence so that it has the same meaning to the first one :
1. I think it would be a good idea to take the train.
=> I suggested ......................
2. She went out, nut she didn't say a word.
=> She went out without ............
3. I often go to bed late.
=> I am used ..............
4. What about going to the cinema tonight ?
=> Shall we ................ ?
5. " Why don't you go with me ? ", he asked me.
=> He asked me why ..............
6. She enjoys going swimming.
=> She is interested in ...............
7. Does he spend most of his free time playing video games ?
=> Does it take .............. ?
8. Does it take you 3 hours to do this task ?
=> Do you spend .............. ?
9. Lan didn't have breakfast, so she is very hungry now.
=> Because Lan ................
10. Ho Chi Minh City is the largest city in Viet Nam.
=> No cities ................

Rewrite the following sentences using given words or phrases :
1. " Don't forget to bring your passport with you tomorrow. " - She reminded me ...............
2. " Would you like me to help to go camping with us next weekend?" said Minh to Phong. - Minh inviteed ....................
3. " Would you like me to clean the room for you ?" she said. - She offered ...............
4. Why didn't you help your mother when she was ill ? - You should ...............
5. "Would you like me to help you with the cooking, Tom ?" Laura said. - Laura offered ....................
6. " Don't forget to prune the roses" said my aunt. - My aunt reminded ..................
7. " Why don't you go and see "The Sound of Silence" again, Brian ?", I said. - I suggested ................
8. " Don't forget to join in the contest tomorrow morning " Lan said. - Lan reminded ....................
9. " Helen, ,would you like to come to lunch on Sunday?", said Mary. - Mary invited ..................
10. " Don't forget to buy some milk, Andy" said Clare. - Clare reminded .............
11. She said "It's good if you make your own decision." (advised)
12. " Why don't you read that book, Peter ?" she said. - She suggested ..............
13. "Try again, all of you" he said. (encourage)
14. " I am sorry. I've made the house untidy" said the girl. (apologize)
15. "Would you like me to lool after the house for you?" he said. (offer)
16. "Shall we meet outside the cinema after eight " he said. (suggest)
17. "Will you have a drink?" he said. (invite)
18. " You had better hurry" she said. (advise)
19. " Do come and enjoy tea with my family " she said. (invite)
20. "Why don't we come to visit our teacher today?" he said. (suggest)
21. " My advise to you is to do morning exercises " she said. (advise)
22. " In your place, I would learn English " she said to me. (advise)