had not 的缩写

had not 的标准缩写形式是 hadn't。

这是英语中常见的助动词 had 与否定词 not 的缩略组合，广泛用于过去完成时（Past Perfect Tense）的否定句中。

基本结构

完整形式：
subject + had + not + past participle

缩写形式：
subject + hadn't + past participle

例句对比

• 完整句：She had not finished her homework.
  缩写句：She hadn't finished her homework.
• 完整句：They had not seen the movie before.
  缩写句：They hadn't seen the movie before.
• 完整句：I had not eaten breakfast when you called.
  缩写句：I hadn't eaten breakfast when you called.

使用场景

hadn't 主要用于表达在过去某一时间点之前尚未完成的动作或状态，常见于：

• 叙述过去的经历（如讲故事）
• 解释因果关系（“因为没做某事，所以……”）
• 与另一个过去动作进行时间对比