Modal verbs of obligation: 应该 (should), 必须 (must), 得 (děi - have to)

Pattern

• Subject + 应该/必须/得 + Verb phrase

Usage

• These three modal verbs express increasing degrees of obligation:
• 1.
• 应该 (yīnggāi - 'should / ought to'): expresses advice, reason, or moral duty: 你应该多锻炼身体 (You should exercise more).
• Negative: 不应该 (should not).
• 2.
• 必须 (bìxū - 'must / have to'): expresses strict, non-negotiable obligation (common in rules and formal speech)

Examples

1. 1

   你应该多锻炼身体。

   Nǐ yīnggāi duō duànliàn shēntǐ.

   You should exercise more.

2. 2

   学生必须按时交作业。

   Xuéshēng bìxū ànshí jiāo zuòyè.

   Students must hand in their homework on time.

3. 3

   时间不早了,我得走了。

   Shíjiān bù zǎo le, wǒ děi zǒu le.

   It's getting late; I have to go now.