Câu hỏi: Although most species of small birds gather in groups at feeders provided by bird-watchers, the bright red cardinals usually appears alone or with its mate.

A. at

B. cardinals

C. or

D. its

Câu 1: Proteins are made up of folded irregularly chains, the links of which are amino acids.

A. made up of

B. folded irregularly

C. the links

D. which

Câu 2: If they took their language lesson seriously, they would be able to communicate with the locals now.

A. took

B. seriously

C.  would be

D. with the locals

Câu 3: It is very difficult for her to prevent him for smoking in her house.

A. very

B. for 

C. prevent 

D. for smoking

Câu 4: Neither William or his brother stole the rambutans from our orchard.

A. or 

B. stole 

C. from

D. our orchard

Câu 5: The bones of the elderly are more prone to fractures than of young people.

A. the elderly 

B. more

C. to

D. of

Câu 6: Each of the members of the group were made to write a report every week.

A. were

B. members

C. to write

D. week