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

A. therefore

B. similarly 

C. on the contrary

D. otherwise

Câu 1: My parents    ........... in Florida since 1999.

A. has lived

B. have lived

C. are living

D. live

Câu 2: Louise was listening to the radio while she .................. the house.

A. is cleaning

B. was cleaning

C. had cleaned

D. will dean

Câu 3: I .............. Michael for years.

A. have known

B. know

C. knowing

D. was known

Câu 4: Paul and Linda .............. us to their party last weekend.

A. was inviting

B. invited

C. had been inviting

D. will invite

Câu 5: The telephone .............. ten times before Patsy finally answered it.

A. rings

B. ringing

C. had rung

D. is ringing

Câu 6: Rita .................. class every day.

A. not to attend

B. doesn’t attend

C. not attending

D. isn’t attended