had not 的缩写形式：hadn't

什么是 “had not” 的缩写？

“had not” 的标准缩写形式是 hadn't。它用于构成过去完成时（Past Perfect Tense）的否定句。

基本结构

肯定句：
Subject + had + past participle

否定句：
Subject + hadn't + past participle

例句

• She hadn't finished her homework when I called.
• They hadn't seen the movie before last night.
• I realized I hadn't locked the door.

常见错误

注意不要将 hadn't 与 didn't have 混淆。前者用于过去完成时，后者用于一般过去时。

• ✅ I hadn't eaten breakfast.（过去完成时）
• ✅ I didn't have breakfast.（一般过去时）