Nêu các thí nghiệm : Lai 1 cặp tính trạng , Lai 2 cặp tính trạng của MenĐen (cứu với )

Cho các số x và y có dạng: x = a1√2 + b1 và y = a2√2 + b2, trong đó a1, a2, b1, b2 là các số hữu tỉ. Chứng minh:

a. x + y và x.y cũng có dạng a√2 + b với a và b là các số hữu tỉ

b. x/y với y ≠ 0 cũng có dạng a√2 + b với a và b là các số hữu tỉ.

22. They expect that the government will lose the election.

a. The government is expected to have lost the election.   b. The government is expected to lose the election.

c. They expect the government to lose the election.         d. They expect the government have lost election.

23. They think that the prisoner escaped by climbing over the wall.

a. The prisoner is thought to escape by climbing over the wall.

b. The prisoner is thought escaped by climbing over the wall.

c. The prisoner is thought having escaped by climbing over the wall.

d. The prisoner is thought to have escaped by climbing over the wall.

24. They believer that the thieves got in through the kitchen window.

a. The thieves are believed to have got in through the kitchen window.

b. The thieves are believed to get in through the kitchen window.

c. They believe the thieves got in through the kitchen window.

d. They believe the thieves have got in through the kitchen window.

17. People say that he is very rich

A. He is said to be very rich.                          

B. He is said to have been very rich.

C. He was said to be very rich.                       

D. He was said to have been very rich.

18. People think that he was born into a rich family.

A. He is thought to have been born into a rich family   

B. He is thought to be born into a rich family.

C. People think his family is rich, so he was born.

19. People rumoured that her husband had died in the battle.

A. Her husband is rumoured to die in the battle.     

B. Her husband died in the battle, and it is the truth.

C. People knew that her husband died in the battle.  

D. Her husband was rumoured to have died in the battle.

20.. They say that many people are homeless after the tsunami.

a. They say many people to have been homeless after the tsunami.

b. They say many people to be homeless after the tsunami.

c. Many people are said to have been homeless after the tsunami.

d. Many people are said to be homeless after the tsunami.

21. They know that the Prime Minister is in favour of the new law.

a. The Prime Minister is known to have been in favour of the new law.

b. They know the Prime Minister to be in favour of the new law.

c. The Prime Minister is known to be in favour of the new law.

d. They know the Prime Minister to have been in favour of the new law.

11. They reported that the troops were coming.

A. It had been reported that the troops were coming.  

 B. It was being reported that the troops were coming.

C. It was reported that the troops to be coming.             

D. It was reported that the troops were coming.

12. Many people think Steve stole the money.

A. It was not Steve who stole the money.         

B. Steve is thought to have stolen the money.

C. Many people think the money is stolen by Steve.    

D. The money is thought to be stolen by Steve.

13. People believed he won a lot of money on the lottery.

A. He is believed that he won a lot of money on the lottery.  

B. He won a lot of money on the lottery, it is believed.

C. He is believed to have won a lot of money on the lottery.

D. He was believed to win a lot of money on the lottery.

14. People say that prevention is better than cure.

A. That prevention is said is better than cure.                

B. It is s id that prevention is better than cure.

C. Prevention is better that cure is said by people.         

D. Prevention says to be better than cure.

15. People think that an apple a day is good for you.

A. It is thought that an apple a day is good for you.          

B. It was thought that an apple a day is good for you.

C. They are thought that an apple a day is good for you.    

D. They thought that an apple a day is good for you.

16. People say that they bought this shop last year.

A. It was said that they bought this shop last year.              

B. They are said to buy this shop last year.

C. It is said that they bought this shop last year.                  

D. They were said to have bought this shop last year.

8. They think that the prisoner escaped by climbing over the wall.

A. The prisoner is thought to escape by climbing over the wall.           

B. The prisoner is thought escaped by climbing over the wall.

C. The prisoner is thought having escaped by climbing over the wall.     

D. The prisoner is thought to have escaped by climbing over the wall.

9. They believe that the thieves got in through the kitchen window.

A. The thieves are believed to have got in through the kitchen window.     

B. The thieves are believed to get in through the kitchen window.

C. They believe the thieves got in through the kitchen window.            

D. They believe the thieves have got in through the kitchen window.

10. They report that over 200,000 people were killed in the tsunami.

A. Over 200,000 people are reported to have been killed in the tsunami.      

B. Over 200,000 people are reported to be killed in the tsunami.

C. Over 200,000 people are reported to have killed in the tsunami.            

D. Over 200,000 people are reported to kill in the tsunami

People think that he was born in a rich family.

A. That is thought he was born in a rich family.  

B. He was thought to be born in a rich family.

C. That he was born in a rich family is thought.  

D. He is thought to have been born in a rich family.

5. They said that the president had arrived in the city.

A. The president was said to have arrived in the city

B. It is said that the president had arrived in the city.

C. The president was said to arrive in the city.

D. It was said that the president arrived in the city.

6. He expects that his father will come back home.

A. It was expected that his father will come back home.  

B. His father was expected to be come back home.

C. His father will be expected to come back home.        

D. His father is expected to come back home.

7. They said that he was all right .

A. He said he was all right.                      

B. They were said him was all right .

C. He was said he was all right.               

D. He was said to be all right

Ex1 . Choose the best answer. 

1 They think that he has died a natural death.

A, It is thought that he has died a natural death.     

 B, They thought that he died a natural death.

C, He is thought to have died a natural death.          

D, A & C are correct

2. They say that John is the brightest student in class.

A, They said that John is the brightest student in class.

B, They said that John to be the brightest student in class.

C, John is said to be the brightest student in class.       

D, It is said that John to be the brightest student in class.

3.People say that the American women are used to living independently means

A. It is said that the American women are used to living independently.

B.The American women are said to be used to living independently.

C.The American women are said they be used to live independently.                  

 D.A & B are correct

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