III. Ex:

1. I hate ( answer )………ANSWERING………the phone, sometimes I let it ( ring )……RING…….

2. We ( know )…………HAVE KNOWN………each other for 12 years, since we ( be ) …HAVE BEEN….. in class1.

3. They like ( lie )……LYING……..on the beach, they usually spend their holidays ( sunbathe) ………SUNBATHING………….

4. Our teacher asked us ( not talk )………NOT TO TALK………….in the class.

5. He wishes He ( be )………WERE………….taller.

6. This kind of jacket ( just / sell )……HAS JUST BEEN SOLD……………….

7. If you ( not understand )…………DON'T UNDERSTAND……………., I ( help )……WILL HELP………….you.

8. We ( be )……WILL BE………….late, if we ( not hurry )……DON'T HURRY…………………

9. They started ( learn )……LEARNING………… four years ago.

10. It is too expensive for me ( buy )………TO BUY…………..that dictionary.

11. If the weather ( be )……IS …….fine, we ( go )……WILL GO…….for a picnic.

12. My friend ( call )………CALLED……..me last night but I ( not be )……WASN'T………….at home, so I ( phone ) ………AM PHONING…………her this evening.

13. She was tired so she had to ( stay )…………STAY………..at home.

14. My parents decided ( buy )……TO BUY……………a new house in Dong Xoai.

15. These boys feel excited ( have )…………OF HAVING……….a trip to Dai Nam.

16. Mai ( play )………HAVE PLAYED…………tennis for school team since she ( be )……WAS……12.

17. He said they ( finish )………WOULD FINISH………………..their homework the next day.

18. I am interested in ( live )……LIVING………………in the countryside.

19. When Hoa ( come )………CAME………..to my house, I ( read )………WAS READING…..a new book.

20. What about ( raise )…RAISING……………..fund for the poor and homeless people?

IV. Rewrite these sentences:

1. Lan isn’t here now and I want she is here.

-> I wish LAN WERE HERE

2. We can’t go out because it is raining.

-> We wish WE COULD GO OUT

3. It’s a pity I can’t speak English well.

-> I wish I COULD SPEAK WELL

4. He likes playing soccer.

-> He is GOOD AT PLAYING SOCCER

5. She is too young to go to school alone.

-> She is not OLD ENOUGH TO GO TO SCHOOL ALONE

6. Reading book gives me pleasure.

-> I AM INTERSETED IN READING BOOK

7. Tuan is too short to play volleyball.

->Tuan wishes TUAN WERE TALLER TO PLAY FOOTBALL

8. The journey to Ba’s village is interesting.

-> It is AN INTERESTING JOURNEY TO BA'S VILLAGE

Cho hai tập hợp A và B

CMR:A=B khi và chỉ khi B=A

\(C=\left(x+3\right)\left(x+1\right)\)

\(=x^2+4x+3\)

\(=\left(x+2\right)^2-1\)

Ta có:\(\left(x+2\right)^2\ge0\)

\(\Leftrightarrow\left(x+2\right)^2-1\ge-1\)

Dấu ''='' xảy ra khi \(x+2=0\Leftrightarrow x=-2\)

Vậy GTNN của A là -1 khi x=-2

chac chan la 5 minh vua thi xong

do mình nhầm

Tìm x

\(\left(\sqrt{x}+\frac{1}{\sqrt{x}+1}\right).\left(1-\frac{\sqrt{x}+2}{x+\sqrt{x}+1}\right)>0\)

ĐKXĐ:x\(\ne\)0

\(\Leftrightarrow\frac{x+\sqrt{x}+1}{\sqrt{x+1}}.\frac{x+\sqrt{x}+1-\sqrt{x}-2}{x+\sqrt{x}+1}>0\)

\(\Leftrightarrow\sqrt{x}-1>0\)

\(\Leftrightarrow x>1\)