Câu hỏi: Teddy Roosevelt demonstrated his competitive spirit and tireless energy in 1905 whenever he led the Rough Riders up San Juan Hill.

A. demonstrated

B. competitive

C. whenever

D. he

Câu 1: Unless there had been a heavy storm, the climbers will not have died.

A. Unless

B. had been

C. heavy

D. will

Câu 2: When a patient's blood pressure is much higher than it should be, a doctor usually insists that he will not smoke.

A. much

B. than it

C. should be

D. will not

Câu 3: The puppy stood up slowly, wagged its tail, blinking its eyes, and barked.

A. slowly

B. its

C. blinking

D. and

Câu 4: He was very surprised when he visited London, in that the drivers always drive on the left hand side of the street.

A. very surprised

B. when

C. in that

D. on

Câu 5: Collecting stamps, playing chess and to mount beautiful butterflies are derrick’s hobbies.

A. collecting

B. playing

C. to mount

D. are

Câu 6: Ecologists are trying to preserve our environment for future generations by protecting the ozone layer, purifying the air, and have planted the trees that have been cut down.

A. to preserve

B. for

C. the ozone layer

D. have planted