Only recently _____to realize the dangers caffeine might bri

来源：学生作业帮编辑：作业帮分类：英语作业时间：2024/05/12 09:58:50

Only recently _____to realize the dangers caffeine might bring to our health .
A.that scientists began B.have scientists begun
C.scientist have begun D.that did scientist begin
正确答案为B,可是D为什么不行?
首先only用于句首，句子要用倒装形式，而且是部分倒装。从句中的might用了过去式，由此可以推断出主句要用过去的过去即过去完成时。
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哪来的过去完成时

你认为caffeine might bring to our health 是发生在realize之后吗?
这是逻辑的错误,
咖啡因对我们身体有好处是比我们发现还要早,我们发现是在他对我们有好处之后才出现的..所以不需要..

Only recently _____to realize the dangers caffeine might bri smokers will realize the dangers of smoking one day. The Dangers from Noise Only后面的倒装only then,only recently,only in the last year,only Only then did she realize the stress he was under. Only then did I realize the importance of English.语法分析 I realize the value only after I lose it. only when you realize the importance of foreign languages___ Only recently----to deal with the environmental problems. ---Not only _____to Beijing,but I've also climbed the Great the dangers of 和the danger of Only when he reached the tea-house did he realize it was the