59.He was ______ what to do.

来源：百度知道 编辑：UC知道 时间：2024/04/30 10:08:58
a. at his wit end b. at his wits end c. at his wit’s end d. at his wits’s end

请高手给个确切的答案，讲下集中的语法知识，再翻译下句子，谢谢！

C at his wit's end wit = 不可数单词

算是一句英文惯用成语。等于是“不知道该怎么做尽管你绞尽脑汁”
一般如果单独的话就是 to be at one's wit's end
to be 就是is， was, are, were这些

wit智慧,智慧不可数是吧，排除掉B和D
再看what to do 是一个完整的结构，而且what是名词，那么名词词性的end讲不通，所以是动词的end

C at his wit's end 是固定短语,不用想了.
e.g.
At my wit's end; at their wits' end