"Fail to do sth." 是一个英语短语,表示没有成功地完成或达到预期的目标。它通常用于描述尝试但未实现的情况,包含了失败、未达成或者疏忽的意思。这个短语可以用在各种语境中,无论是正式还是非正式,表达一种负面的结果。

### 用法

1. **动词短语**: "fail to do sth." 常作为动词短语使用,其主语通常是执行动作的人或事物。

   - 例如:I failed to finish the project on time.(我没能按时完成项目。)

2. **否定形式**:这个短语本身就是一个否定含义,因此在句子中不需要再使用否定词如 "not"。

   - 例如:She didn't fail to notice his strange behavior.(她注意到了他奇怪的行为。)

3. **比较级与最高级**:"fail to do sth." 可以与 "more/less likely to fail to do" 或 "the most/least likely to fail to do" 结合,表示可能性的比较或最高级。

   - 例如:They are less likely to fail to meet the deadline than we expected.(他们比我们预料的更有可能按时完成。)

### 例句

1. Despite his best efforts, he failed to convince her of his innocence.(尽管他竭尽全力,还是未能说服她他是无辜的。)

2. The team failed to qualify for the tournament due to their poor performance.(由于表现不佳,队伍未能晋级比赛。)

3. She consistently fails to understand the complex instructions, which frustrates her colleagues.(她总是无法理解复杂的指示,这让她的同事们感到沮丧。)

4. He almost forgot to mention an important detail in his report, but managed to recall it at the last minute. (他几乎忘了在报告中提到一个重要细节,但在最后一刻想起来了。)

### 同义词辨析

1. **be unable to do sth.**:这个短语也表示不能做某事,但通常强调的是能力不足或外界条件不允许,而不是个人努力失败。

   - 例如:Due to the injury, he was unable to play in the match.(因为受伤,他无法参加比赛。)

2. **not manage to do sth.**:这个短语同样表示尝试但未成功,但语气较轻,可能暗示了某种尝试或努力。

   - 例如:I didn't manage to find the book you recommended in the library.(我没能在图书馆找到你推荐的那本书。)

3. **fall short of doing sth.**:这个短语意味着没有达到预期的标准或目标,常用于正式场合。

   - 例如:Our sales figures fell short of the company's projections this quarter.(我们这个季度的销售额未达到公司的预测。)

4. **come up short in doing sth.**:这个短语表示在某个任务或挑战中失利,常用于口语。

   - 例如:She came up short in the final round of the competition.(她在比赛的最后一轮中失利了。)