2022牡丹江统招专升本英语每日一题96

16. It is 50 years ________ the People’s Republic of China was founded.

A.after B.before C.when D.since

16.【题目】D。解析：句意：从中华人民共和国组建到今日有50年了。四个选项均可引导时长副词定语。after在……前;before在……前;when当……时候;since自从。故选D。