Đặc điểm không phải là khó khăn gặp phải khi nghiên cứu di truyền người là

A. người chín sinh dục muộn, số lượng con ít, đời sống của một thế hệ kéo dài

B. không thể áp dụng phương pháp phân tích di truyền như ở các sinh vật khác

C. con người sống di chuyển, thông minh nên biết tránh tất cả các tác động từ môi trường

D. không thể áp dụng phương pháp gây đột biến bằng các tác nhân lí, hóa học, sinh học

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 25 to 29.

The United States has many different types of families. (25) ______ most American families are traditional, consisting of a father, a mother and one or more children, 22 percent of all American families in 1998 were headed by one parent, usually a woman. In a few families in the United States, there are no children. These (26) ___________ couples may believe that they would not make good parents; they may want freedom from responsibilities of childbearing; or, perhaps they are not (27) _______ able to have children. Other families in the United States have one adult who is a stepparent. A stepmother or stepfather is a person who joins a family by marrying a father or a mother.

Americans (28) ___________ and accept these different types of families. In the United States people have right to privacy and Americans do not believe in telling other Americans (29) ______ type of family group they must belong to. They respect each other’s choices regarding family groups. Families are very important to Americans.

Điền vào ô 28

A. tolerate 

B. refuse 

C. remember 

D. remind 

1) She wishes he will stop making noise when she is working. -> would

2) Tom uses to wear glasses, but he doesn't now. -> used

3) This book consusts about three parts: introduction, development and conclusion. -> consusts us

1. Brother / buy / new computer / if / have / enough money.

-> My brother will buy a new computer if he has enough money.

2. Nam / not speak / English / fluent / as / friends.

-> Nam doesn't speak English as fluently as his friends.

3. Liz / not send / us / letter / since / she / return / USA.

-> Liz hasn't sent us a letter since she returned USA.

4. Lot / trees / will / plant / along / streets / students / Ngo Sy Lien High School.

-> Lots of trees will be planted along the streets by the students of Ngo Sy Lien High School.

5. Tet / be / important festival / which / occur / late January / early February.

-> Tet is an important festival which occurs late January and eary February.

-> Do you know the girl who has black curly hair?

It (be) was a sunny day.Helen (walk) walked to the park.In the park she (phone) phoned her friend Daisy.Helen (wait) waited for 15 minutes and Daisy (arrive) arrived.The girls (walk) walked to the river .There (be) were two boys there.Suddenly the big boy (push) pushed the small boy into the river.Helen (jump) jumped into the river to rescue the boy.Daisy (phone) phoned the ambulance and the police.The doctors and police (arrive) arrived.They (interview) interviewed the girls.