What enables some people to get big creative breakthroughs while others only get small and non-creative breakdowns, blaming themselves and society? Are some people "gifted"? Are there other factors __21__ work--factors that we have more control over than we think?

While nobody can deny the __22__ that some people seem to be blessed with particular creativity, research shows that anyone can __23__ their chances of coming up with new and original ideas __24__ they would only engage themselves more in the process of __25__. It&39; s the old Thomas Edison thing about "discovery__26__ 99 percent perspiration (汗水) and 1 percent inspiration. " __27__ , the studies prove this:great creative breakthroughs usually happen only __28__ intense periods of struggle. It is sustained effort towards a specific goal __29__ eventually prepares for great creative insights.

This kind of sustained effort does not always __30__ immediate results, a fact that not only separates the innovators (革新者) from non-innovators, but __31__leads some people to conclude that it is just not __32__ for them. "Maybe I should have gone to medical school like my mother wanted," they wonder when the breakthrough is __33__ to be found. Alas, one forgets during inevitable encounters __34__self-doubt,that the big surprise is never __35__. Indeed,it can happen at any time and place.

21______

A．to

B．in

C．at

D．by

22A.issue

B．problem

C．reason

D．fact

27A.Sooner or later

B．Some day or other

C．Every now and then

D．Time and again

28A.beyond

B．after

C．above

D．through

29A.that

B．who

C．what

D．as

30

A．create

B．produce

C．inspire

D．encourage

31A.too

B．once

C．again

D．also

33A.anywhere

B．everywhere

C．somewhere

D．nowhere

34A.against

B．across

C．with

D．into

35A.far away

B．used up

C．cleared off

D．near by

23A.miss

B．reduce

C．increase

D．lose

32A.good

B．difficult

C．possible

D．stupid

24A.because

B．if

C．while

D．whether

25A.creation

B．practice

C．production

D．achievement

26A.being

B．be

C．was

D．were

请帮忙给出每个问题的正确答案和分析，谢谢！