Question

【题目】They use computers to keep the traffic smoothly. k

A. being run B. run

C. to run D. running

Answer 1

【答案】D

【解析】

试题分析：这儿构成“keep+宾语+doing”固定用法。现在分词作动词keep的宾语补足语。traffic与run之间是主动关系，所以用现在分词。