I had failed for several times.其中for的用法是什么

I had failed for several times.其中for的用法是什么 They had failed to locate the ship they had been sent to look for.翻译. 翻译：“for the third time in a row ,she had failed to keep her appointment” （ ）I failed in English a third time,I had no doubt about my gift for foreign languages.A.By the time B.Until C.After D.Unless正确答案是B,为什么不是D,unless=if not Sir,I wouldn'd ask for a day off if I feel__.You know ,my son is running a high fever.A.used to B.happened C.failed to D .had toThank you. I'm very furstrated when I heard that I had failed the exam.为什么这里用 furstrated 刚拼错单词了~I'm very frustrated when I heard that I had failed the exam.为什么这里用 frustrated I failed my math i failed u --I failed again.I wish I __ harder.--But you __.A.had worked,hadn't B.had worked,didn't For The Heart I Once Had 歌词 I thought you had feelings for me. whatdid you have for dinner?i had? I had no money for a car I had a thing for you Tom failed again ,____ I had said .A.like B.that C.as D.which为什么选C呢 关于虚拟从句的倒装问题If you had not helped me,I should have failed.要是没有你的帮助,我就失败了.可以改为Had you not helped me,I should have failed.那么可以把虚拟从句放在主句背后吗：I should have failed,had ---- Mary,how did your Math test go ---- I had thought I ______,but in fact I came in the top 10A.should have failed B.could have failed C.might have failed D.need have failed为什么选c 不选b i am hungry.I only had some p____ for breakfast