Auxiliary verb

Also known as: modal verb, 助动词 (zhùdòngcí), 情态动词 (qíngtài dòngcí) and 能愿动词 (néngyuàn dòngcí).

Auxiliary verbs are helping verbs that come before main verbs and help express the tone or mood of the verb. (The word "modal" comes from "mood.") In English, these are things like "should", "will" and "can", which all change something about the situation and the speaker's attitude. Auxiliary verbs express capability, possibility, necessity, obligation or willingness.

Characteristics

In sentences with auxiliary verbs, the auxiliary verb is the one that gets modified. That is, if you want to negate a sentence with an auxiliary verb, put "不" before the auxiliary, not the main verb.

Also, unlike normal verbs, auxiliary verbs can't be reduplicated, nor can they take the aspect particles: 了 (le), 着 (zhe), and 过 (guo).

Finally, when you are responding to a question that uses an auxiliary verb, you reply with the auxiliary verb, not with the main verb that it modifies.

Sources and further reading

• 外国人实用汉语语法(中英文对照) (pp. 41 - 47)
• Basic Patterns of Chinese Grammar (pp. 81 to 89)
• 简明汉语语法学习手册 (Chinese Grammar Without Tears) (pp. 239 - 250)
• Practicing HSK Grammar (pp. 141 - 151)
• Modern Mandarin Chinese Grammar: A Practical Guide (pp. 69 - 75)
• 40 Lessons for Basic Chinese Course (基础汉语40课上册） (p. 140)→buy