Câu hỏi: An endangered species is the one _________ population is so small that it is in danger of becoming extinct.

A. which

B. what

C. whose

D. who

Câu 1: George is not enough intelligent to pass this economics class without help.

A. enough intelligent

B. to pass

C. economics

D. help

Câu 2: After David _________ his homework, he went straight to bed.

A. had finished

B. has finished

C. was finished

D. finished

Câu 3: "Be sorry for sending the wrong information, Kate" said Rita.

A. Kate sent the wrong information, and she was sorry.

B. Rita apologized to Kate for sending her the wrong information

C. Rita was sorry about Kate's sending the wrong information.

D. Rita was sorry for not sending Kate the information.

Câu 4: We should participate in the movement _________to conserve the natural environment.

A. which organized

B. organizing

C. to organize

D. organized

Câu 5: While Peter ________the rose bush in the back yard, the phone rang.

A. were watering

B. has watered

C. watered

D. was watering

Câu 6: Some snakes have hollow teeth they are called fans that they use to poison their victims.

A. Some 

B. they are called

C. use

D. their