祈使句 (imperatives) 用来下命令、给指示或提请求。直接用动词原形开头，不要主语。
打开Open （冠词）the 门door 请, please.
Vui lòng mở cửa ra.
坐Sit 下down.
Ngồi xuống.
否定: 前面加 Don't。
不要Don't （是）be 迟到late.
Đừng đến muộn.
Điểm chú ý về cách dùng:
- 加 please 更礼貌: Please come in. (请进。)
- 也用于路线、说明: Turn left. (向左转。) Mix the eggs. (把鸡蛋打匀。)
注意 祈使句不写主语: ~~You open the door~~ (命令时) → Open the door.
Lỗi thường gặp
- ❌ ~~Please open door.~~ → ✓ Please open the door. — 祈使句里冠词照样不能丢。
- ❌ ~~Don't to touch it.~~ → ✓ Don't touch it. — don't 后面直接跟动词原形，不加 to。
- ❌ ~~No talk in class!~~ → ✓ Don't talk in class! / No talking! — 禁止做某事用 don't + 原形；no 后面要用 -ing 或名词。
- ❌ ~~You sit down!~~ → ✓ Sit down, please. — 加了 you 的命令听起来很生气；想礼貌就加 please，或改问 Can you…?