Câu hỏi: It is recommended that people to take regular exercise.

A. recommended

B. people

C. to take

D. exercise

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: 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 3: More than ten students have failed the exam, that surprised the class teacher.

A. more than

B. have failed

C. that

D. the

Câu 4: My elder sisters, both of them were doctors, said they were too busy to pick me up.

A. elder

B. both of them

C. too busy 

D. to pick

Câu 5: Tenant farmers are those they either rent a farm and work it for themselves or work the farm for the owner and receive payment.

A. they

B. it

C. or

D. the owner

Câu 6: 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