二、动词时态

1. Europeans have long known that eating quail sometimes makes the eater ill, but only recently has it been established that the illness is caused by a toxin present in the quail’s body only under certain conditions.

A) Europeans have long known that eating quail sometimes makes

B) Europeans have long known quail eating is sometimes able to make

C) Eating quail has long been known to Europeans to sometimes make

D) It has long been known to Europeans that quail eating will sometimes make

E) It has long been known to Europeans that quail, when it is eaten, has som etimes made

2． Interest rates on mortgages have declined steadily during the first six months of this year but virtually remained unchanged during the next three months.

A) have declined steadily during the first six months of this year but virtually remained unchanged

B) declined steadily during the first six months of this year but virtually remain unchanged

C) steadily declined during the first six months of this year but remain virtually unchanged

D) declined steadily during the first six months of this but have remained virtually unchanging’

E) declined steadily during the first six months of this year but have remained virtually unchanged

3． Although the Supreme Court ruled as long ago as 1880 that Blacks could not be excluded outright from jury service, nearly a century has been necessary to develop and enforce the principle that all juries must be drawn from “ a fair cross section of the community”

A） has been necessary to develop and enforce the principle that all juriesmust be

B） was necessary for developing and enforcing the principle that all juries must be

C） was to be necessary in developing and enforcing the principle of all furies to be

D） is necessary to develop and enforce the principle that all juries must be

E） will be necessary for developing and enforcing the principle

4.Some buildings that were destroyed and heavily damaged in the earthquake last year were constructed in violation of the city’s building code.

A) Some buildings that were destroyed and heavily damaged in the earthquake last year were

B) Some buildings that were destroyed or heavily damaged in the earthquake last year had been

C) Some buildings that the earthquake destroyed and heavily damaged last year have been

D) Last year the earthquake destroyed or heavily damaged some buildings that have been

E) Last year some of the buildings that were destroyed or heavily damaged in the earthquake had been

5. by the time peace and happiness will have come to the planet, many lives will be wasted.

A) will have come to the planet, many lives will be wasted

B) come to the planet, many lives will have been wasted

C) will have come to the planet, many lives will have been wasted

D) shall have come to the planet, many lives shall be wasted’

E) would have come to the planet, many lives would have been wasted

6. the books of W.E.B. DuBois before World War I constituted as fundamental a challenge to the accepted ideas of race relations that, two generations later will be true of the writings of the radical writers of the 1960’s.

A) that, two generations later will be true of

B) that, two generations later, would be true of

C) as, two generations later , would be true of

D) as, two generations later, would

E) just in the way that, two generations later, did

7.While everyone continues to hope for their survival, it is unlikely that the astronauts could have made it back to the shelter before the power plant exploded.

A) could have made it back to the shelter before the power plant exploded

B) were making it back to the shelter before the power plant exploded

C) were able to make it back to the shelter before the power plant explodes

D) have been able to make it back to the shelter before the power plant will explode

E) could have made it back to the shelter before the power plant would have destroyed them

8.parliament did not accord full refugee benefits to twelve of the recent im migrants because it believed that to do it rewards them for entering the country illegally.

A) to do it rewards

B) doing it rewards

C) to do this would reward

D) doing so would reward

E) to do it would reward

9.for many people, household labor remains demanding even if able to afford household appliances their grandparents would find a miracle.

A) even if able to afford household appliances their grandparents would find a miracle

B) despite being able to afford household appliances their grandparents woul d find a miracle

C) even if they can afford household appliances their grandparents would hav e found miraculous

D) although they could afford household appliances their grandparents would find miraculous

E) even if they are able to afford household appliances which would have been a miracle to their grandparents

10. a huge flying reptile that died out with the dinosaurs some 65 million years ago , the Quetzalcoatlus had a wingspan of 36 feet, believed to be the largest flying creature the word has ever seen.

A) believed to be

B) and that is believed to be

C) and it is believed to have been

D) which was, it is believed,

E) which is believed to be

11. In virtually all types of tissue in every animal species, dioxin induces the production of enzymes that are the organism’s trying to metabolize, or render harmless, the chemical that is irritating it. (O.P.298)

A) trying to metabolize, or render harmless, the chemical that is irritating it

B) trying that it metabolize, or render harmless, the chemical irritant

C) attempt to try to metabolize, or render harmless such a chemical irritant

D) attempt to try and metabolize, or render harmless, the chemical irritating it

E) attempt to metabolize, or render harmless, the chemical irritant