dnf巨龙材料:请高手帮帮忙，解答以下这些题目，最好标上详细注解。谢谢了

16,_____their differences, the couple were developing an obvious and genuine affection for each other.
A,But for B,For all C,Above all D,Except for
17,The manager spoke highly of such____as loyalty,courage and truthfulness shown by his employees.
A,virtues B,features C,properties D,characteristics
18,You don't have to be in such a hurry,I would rather you____on business first.
A,would go B,will go C,went D,have gone
19,When I try to understand____that prevents so many Americans from being as happy as one might expect,it seems to me that there are two causes.
A,why it does B,what it does C,what it is D,why it is
20,Ann never dreams of____for her to be sent abroad very soon.
A,there being a chance B,there to be a chance C,there be a chance D,being a chance
21,Frequently single-parents children____some of the functions that the absent adult in the house would have served.
A,take off B,take after C,take in D,take on
22,There are few electronic applications____to raise fears regarding future employment opportunities than robots.
A,likely B,more likely C,most likely D,much likely
23,John Dewey believed that education should be a preparation for life,that a person learns by doing,and that teaching must____the curiosity and creativity of children
A,seek B,stimulate C,shape D,secure
24,As early as 1647 Ohio made a decision that free,tax-supported schools must be established in every town____50 households or more.
A,having B,to have C,to have had D,having had
25,The suggestions that the mayor___the prizes was accepted by everyone.
A,would present B,present C,presents D,ought to present
26,_____in a recent science competition, the three students were awarded scholarships totaling $21,000.
A,Judged the best B,Juding the best C,To be judged the best D,Having judged the best
27,So many managers____, the board meeting had to be put off
A,were absent B,been absent C,had been absent D,being absent
28,The millions of calculations involved,had they been done by hand,____all practical value by the time they were finished
A,had lost B,would lose C,would have lost D,should have lost
29,It is important that the hotel receptionist____that guests are registered correctly.
A,has made sure B,made sure C,must make sure D,make sure
30,The bank is reported in the local newspaper___in broad daylight yesterday.
A,being robbed B,having been robbed C,to have been robbed D,robbed