求解下列选择Structure A1． Sir Denis,who is 78,has made it known th

求解下列选择
Structure A
1． Sir Denis,who is 78,has made it known that much of his collection ______ to the nation.
A) has left B) is to leave
C) is to be left D) leaves
2.Until then,his family _______ from him for six months.
A) didn’t hear B) hasn’t been hearing
C) hadn’t heard D) hasn’t heard
3.Sometimes very young children have trouble ______ fact from fiction and may believe that such things actually exist.
A) having separated B) to separate
C) separating D) for separating
4.Tryon was extremely angry,but cool-headed enough to ________storming into the boss’s office.
A) turn B) prohibit
C) avoid D) prevent
5.The second book was ______ by August 1952,but two years later,the end was still nowhere in sight.
A) to have completed B) to complete
C) to have been completed D) completed
6.The room is in a terrible mess; it ______ cleaned.
A) wouldn’t have been B) can’t have been
C) mustn’t have been D) shouldn’t have been
7.By success I don’t mean ______ usually thought of when that word is used.
A) that we B) what is
C) as you D) all is
8.Living in the central Australian desert has its problems,_______ obtaining water is not the least.
A) for which B) of which
C) to which D) in which
9.Although many people view conflict as bad,conflict is sometimes useful _______ it forces people to test the relative merits（价值,优点）of their attitudes and behaviors.
A) by which B) in that
C) to which D) so that
10.Never before _______ so highly successful in his attempts to modify the weather on a very small scale.
A) man has been B) has man been
C) man is D) will be man