fail to do与fail (in) sth有什么区别啊

fail in sth..fail to do sth.啥意思? fail to do与fail (in) sth有什么区别啊 never fail to do fail to do fail to do=? fail的几种用法fail in sthfail in doing sthfail to do sthfail sth fail to do sth与forget to do的区别 fail to do sth和fail in doing sth的区别 fail to do sth=? fail to do 还是fail to have done? We do not plan to fail we fail to fail to do和 fail doing有区别没? fail to Fail in plan, is planning to fail什么意思? Fail fail to do sth是未能做某事?还是失败做某事?有没有fail in doing sth? why do you fail to see me? often fail to do英文意思