fail和fail in用法：
1、fail当意思是不及格的时候，是及物动词，后面直接加名词。
2、如果不针对具体的事情，就不用加 in。eg：I failed.
3、如果指具体的事情或者场合就需要加 in。
拓展资料
fail
1. Ever tried. Ever failed. No matter. Try Again. Fail again. Fail better.
努力过，失败过，没关系，屡战屡败，屡败屡战，每一次失败都比上一次更好。
2. Many of Britain's beaches fail to meet minimum standards of cleanliness.
英国许多海滩连最起码的卫生标准都达不倒。
3. The various elements of the novel fail to cohere.
这部小说的各部分之间缺乏连贯性。
4. Those who fail incline to blame the world for their failure.
那些失败者往往将他们的失败归咎于社会。
5. This magnificent church cannot fail to stop you in your tracks.
这座宏伟的教堂一定会让你止步赞叹。
fail in
1. You must study harder ( or ) else you'll fail in the English examination.
你必须努力学习,不然的话,英语考试不会及格的.
2. You will bring the blame of others upon yourself if you fail in this.
如果你在这件事上失败了,就会招来别人的非议.
3. By my calculation, 5 % of the students will fail in the exam.
据我估计, 百分之五的学生不能通过这次考试.
4. I study hard, so that I may not fail in the examinations.
我用功, 免得考不及格.
5. He studied hard only to fail in the exam.
他这么用功,结果竟然考场失利.
6. The ascetic saint and the detached sage fail in this respect to be complete human beings.
禁欲主义的圣徒和超然独处的贤哲在这方面算不上完整的人.
7. Most of us fail in our efforts at self - improvement because our schemes are too ambitious.
我们中的大部分人在 自我 修养的努力中失败了,因为我们的计划过于宏大.
8. I think I'm going to fail in the examinations.
我想我考试会不及格.
9. Drilling techniques that work well in one place can fail in another.
钻探技术可能在一个地方有用,在另一个地方就会失去作用.