He was busing writing a story,only___once ina while to smoke a ci_英语解答

He was busing writing a story,only___once ina while to smoke a cigarette.
A.to stop
B.stopping
C.to have stopped
D.haing stopped
谁能解析一下?

人气：171 ℃　时间：2019-11-12 09:24:59

解答

是B吧
因为要考虑到parallel structure,前面用writing,后面也要跟ing,所以是stopping