【notonlybutalso句首倒装用法】在英语语法中，"not only... but also..." 是一个常见的连接结构，用于强调两个并列的成分。当这个结构出现在句首时，句子需要使用倒装语序，以符合英语的语法习惯。这种倒装结构不仅使语言更加正式和书面化，还能增强语气，突出强调的内容。
一、not only... but also 句首倒装的基本规则
当 "not only... but also..." 放在句首时，句子的主语和谓语需要倒装。其基本结构为：
> Not only + 助动词/情态动词 + 主语 + 谓语 + ... but also + 主语 + 谓语 + ...
例如：
- Not only did he finish the work, but also he helped others.
- Not only is she intelligent, but also she is hardworking.
注意：如果主语是单数名词或代词，助动词用 does；如果是复数，则用 do；如果是过去式，则用 did。
二、常见错误与注意事项
| 错误示例 | 正确形式 | 原因 |
| Not only he finished the work, but also he helped others. | Not only did he finish the work, but also he helped others. | 句首倒装需使用助动词提前 |
| Not only is she smart, but also she is beautiful. | Not only is she smart, but also she is beautiful. | 正确使用了倒装结构 |
| Not only I like apples, but also I love oranges. | Not only do I like apples, but also I love oranges. | 主语是“I”，助动词用“do” |
三、总结
| 项目 | 内容 |
| 结构 | not only... but also... 句首时需倒装 |
| 倒装方式 | 助动词/情态动词 + 主语 + 谓语 |
| 适用情况 | 强调两个并列成分，常用于正式或书面语 |
| 常见错误 | 忽略倒装，直接使用正常语序 |
| 注意事项 | 根据主语选择正确的助动词（do/does/did） |
通过掌握 "not only... but also..." 的句首倒装用法，可以提升英语表达的准确性和正式程度，尤其在写作和口语中显得更加地道。建议多做相关练习，巩固这一语法点。
