fail to do sth解释下.用法什么的,要归纳得好一点.

fail to do sth解释下.用法什么的,要归纳得好一点. fail to do sth=? fail的几种用法fail in sthfail in doing sthfail to do sthfail sth fail in sth..fail to do sth.啥意思? fail to do sth与forget to do的区别 fail to do sth和fail in doing sth的区别 “use to do sth”用法 forget to do sth和fail to do sth 的区别当fail 也意为忘记,时 pass sth to sb fail to do sth 这两个怎么造句啊?pass sth to sb fail to do sth 使役动词的部分用法get/set/leave + sb to do/doing sth是 get/set/leave + sb to do sth get/set/leave + sb doing sth还是get/set/leave + sb to do sth get/set/leave + sb to doing sth请知情者解释下到底是to do与doing之间替换 fail to do与fail (in) sth有什么区别啊 be adj to do sth是什么用法,帮我分析下结构行吗（即to do sth是什么语） try to do sth 与 try doing 用法 讲下 instead 与 instead of 用法是什么? fail to do sth是未能做某事?还是失败做某事?有没有fail in doing sth? 有can't help to do sth这种结构吗?请加以解释用法,意思. need sb to do sth 用法 be able to do sth 意思 用法! be about to do sth的用法