21£®He is a man of _______ and he had a lot of interesting _______ in his life.

A. much experience, experiences     B. many experiences, experience

C. much experience, experience      D. many experiences, experiences

22. To the great      of the young writer£¬his first book sells well after it was published in May.

A£®silence       B£®respect       C£®satisfaction      D£®congratulation

23£®         you study£¬         you will learn.

A£®Harder£»harder                   B£®The more£»the harder

C£®The hard£»the more               D£®The harder£»the more

es “hands-on science” mean in the last paragraph?
A.Science games designed by kids         B.Learning science by doing things
C.A show of kids’ science work           D.Reading science books