As a small boy, he used to _______ alone in the house for an hour or two.

A. being left

B. leaving

C. be left

D. leave

That carcinogenic substances _______ in many common household items is well-known.

A. are contained

B. containing

C. are containing

D. contained

I _______ Lan since she went abroad.

A. wasn’t met

B. hadn’t met

C. didn’t meet

D. haven’t met

Flat-roofed buildings are not very _______ in areas where there is a great deal of rain or snow.

A. severe

B. serious

C. suitable

D. sensitive

I must warn you I am not used to _______ so rudely.

A. speak

B. be spoken

C. speak to me

D. being spoken to

Why not _______ the meeting until Thursday morning?

A. postpone

B. postponing

C. you postpone

D. do you postpone

Susan rarely stays up late, _______?

A. is she

B. isn’t she

C. does she

D. doesn’t she

The scientists _______ on this project try to find the solutions to air pollution.

A. working

B. worked

C. are working

D. who working

I like doing _______ such as cooking, washing and cleaning the house.

A. house-keeper

B. household chores

C. lord of house

D. white house

_______ in large quantities in the Middle East, oil became known as black gold because of the large profit it brought.

A. That when discovered

B. Discovered

C. Discovering

D. Which was discovered