问题补充：
The librarian had to the naughty boy in order to let others concentrate on their books.
A. revolve
B. surround
C. silence
D. adopt
答案：
A. revolve
B. surround
(答案→)C. silence
D. adopt
解析：句意为：图书馆理员为了让其他的读者集中精力读书不得不使那个淘气的小男孩安静下来。revolve vt 使旋转，使循环；surround vt围绕，包围；silence vt 使安静下来，使平静；adopt vt 采取，接受，收养。故答案应为C
