1
fail to do sth
fail 后接动词不定式，表示“未能做成某事”，语气比 didn't do 正式。
He failed to meet the deadline.
他未能赶上截止日期。
失败；未能做到
failing — present participle of fail
先理解核心含义，再看它在真实句子里的用法。
失败；未能做到
To be unsuccessful; especially, not to achieve a goal or intended result.
He failed to meet the deadline.
他未能赶上截止日期。
表示“未能做到某事”时，后接不定式，如 fail to do sth.
不成功
To be unsuccessful.
未达到特定目标(用法说明:该词的直接宾语通常是动词不定式)
Not to achieve a particular stated goal. (Usage note: The direct object of this word is usually an infinitive.)
疏忽；忽略
To neglect.
(机器等)停止正常运转
Of a machine, etc.: to cease to operate correctly.
fail
Base
原形
fails
3rd person
第三人称单数
failing
-ing
现在分词
failed
Past
过去式
failed
Past participle
过去分词
They often fail to meet the deadline.
他们常常无法在截止日期前完成。
She failed the math exam last week.
她上周数学考试没及格。
The company has failed to pay its debts.
这家公司至今未能偿还债务。
规则动词，过去式和过去分词均为 failed；表示“未能做某事”用 fail to do sth.。
She studied hard but failed the exam.
她努力学习，但考试没及格。
The company failed to meet its sales target.
公司未能达到销售目标。
My computer suddenly failed during the presentation.
我的电脑在演示过程中突然出故障了。
fail 后接动词不定式，表示“未能做成某事”，语气比 didn't do 正式。
He failed to meet the deadline.
他未能赶上截止日期。
此时 fail 是及物动词，宾语为人，表示辜负信任或期望。
I won't fail you.
我不会辜负你。
表示考试或测试不及格时，美式英语常用 fail sth，英式英语也可用 fail in sth。
She failed in her driving test.
她驾驶考试没通过。
Not this
He failed to pass the exam.
Use this
He failed the exam.
“fail” 本身已含“未能通过”之意，再与 to pass 连用语义重复。表示“考试不及格”时，直接把考试科目作 fail 的宾语即可。
Not this
She failed noticing the mistake.
Use this
She failed to notice the mistake.
fail 表示“未能做某事”时，须接不定式 to do，不能用动名词；因此应改为 to notice。
Focus on the distinctions below. Other candidates are kept compact until a reliable usage note is available.
未能做
He failed to arrive on time.
他未能按时到达。
考试不及格
She failed the math exam.
她数学考试不及格。
辜负某人
I feel I've failed my parents.
我觉得我辜负了父母。
在…方面失败
He failed in his attempt to climb the mountain.
他攀登那座山的尝试失败了。
忘记提及
She failed to mention the important detail.
她忘记提及那个重要的细节。
未能出庭
The witness failed to appear in court.
证人未能出庭。
必定，一定
You must submit the report by Friday without fail.
你必须在星期五之前务必提交报告。
不明白，不理解
I fail to see why you are upset.
我不明白你为什么难过。
使某人失望
He failed his team by not showing up.
他因为没露面让团队失望了。
我辜负了你，阿纳金。
I have failed you, Anakin.
我辜负了你，阿纳金。
你辜负了这座城市！
You have failed this city!
你辜负了这座城市！
Use failing naturally, then get feedback on meaning, tone, grammar, and phrasing.
Revisit a common error or keep this word in your review list.
fail 读作“飞哦”，想象成功飞走了，就是失败。
动词'fail'可用于多种语境，如学业、工作、设备等。通常为中性语体，但在表达'使某人失望'时带有情感色彩。
表示“未能做某事”时，常接不定式：fail to do sth.
Dictionary facts from ECDICT, WIKTIONARY.