Câu hỏi: Louise was listening to the radio while she .................. the house.

A. is cleaning

B. was cleaning

C. had cleaned

D. will dean

Câu 1: We .............. since 5:00.

A. talk

B. are talking

C. talking

D. have been talking

Câu 2: The telephone .............. ten times before Patsy finally answered it.

A. rings

B. ringing

C. had rung

D. is ringing

Câu 3: We always...................... a present to Elsa on her birthday.

A. are taking

B. taking

C. take

D. are taken

Câu 4: I ................. the house before you called.

A. leave

B. am leaving

C. had left

D. had been leaving

Câu 5: The store ..................... two sales so far this year.

A. is having

B. has been having

C. has

D. has had

Câu 6: The old drainage pipelines must be maintained; ................, leakage will be unavoidable.

A. therefore

B. similarly 

C. on the contrary

D. otherwise