Whenyoudon’tknowsomewordsinreading,itisnotagoodidea    ...

问题详情：

When you don’t know some words in reading, it is not a good idea             in a dictionary at once.

 A. look up them     B. looking up them  

C. to look them up   D. look them up

【回答】

C

知识点：动词和动词短语

题型：选择题