Question

【题目】The police ___________ for the missing girl for a day since they received the call for help.
A.searching
B.have searched
C.searched
D.to search

Answer 1

【答案】B
【解析】句意：自从警察接到求助电话，他们就寻找失踪女孩已经一天了。searching 寻找，搜寻，是动名词形式；have searched现在完成时，已经寻找；searched搜寻，过去式；to search是动词不定式形式。句中since引导的是时间状语从句，从句中用一般过去时态，主句用现在完成时。故应选B。