Theauthorassumesthathisreadersare__________thebasic

The author assumes that his readers are__________ the basic concepts.

A． careful with

B． careful to

C． familiar with

D． familiar to

正确答案：C
无carefulwith／to搭配；befamiliarwith精通熟悉这个短语表示一种主动关系一般用人作主语；befamiliarto众所周知的这个短语表示一种被动关系题干意思：作者认为他的读者很熟悉这些基本的概念