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Experts have been warning _____ of the health risks caused by passive smoking.A.at a timeB.at one ti
题目简介
Experts have been warning _____ of the health risks caused by passive smoking.A.at a timeB.at one ti
题目详情
Experts have been warning _____ of the health risks caused by passive smoking.
A.at a time
B.at one time
C.for some time
D.for the time
题型:单选题难度:偏易来源:不详
答案
C
for some time 意为“一段时间”,因为谓语用了现在完成进行时,所以要用for some time,表示从过去的某个时候开始一直延续到现在的一段时间内,专家一直警告说被动吸烟引起健康危急。at a time意为“每次,在某时”;at one time意为“同时,曾经”;for the time意为“暂时”。
题目简介
Experts have been warning _____ of the health risks caused by passive smoking.A.at a timeB.at one ti
题目详情
答案