Modal verbs, negation and questions 情态动词、否定与疑问句

In the Paper 2 role play the candidate must ASK, and the interrogative must be right. ✗ 你想去多久？(how long) when the task is a price → ✓ 请问，一张票多少钱？(Qǐngwèn, yì zhāng piào duōshao qián?) — How much is one ticket? Match the interrogative to the information: 几点 (time), 多少钱 (how much), 什么时候 (when), 怎么走 (how). Name the word you need, then build the question.

For an action that did NOT happen in the past, use 没, not 不. ✗ 我昨天不去学校 → ✓ 我昨天没去学校。(Wǒ zuótiān méi qù xuéxiào.) — I did not go to school yesterday. The rule: 不 negates a habit, the present/future, an opinion, an adjective or a modal (我不喜欢, 我不会); 没(有) negates a completed action that did not happen. This feeds the spoken past-tense weakness examiners flag.

没 (or 没有) already says the action did NOT happen, so the completion marker 了 cannot sit with it. ✗ 我没吃了饭 → ✓ 我没吃饭。(Wǒ méi chī fàn.) — I have not eaten. ✗ 我昨天没去了 → ✓ 我昨天没去。(Wǒ zuótiān méi qù.) — I did not go yesterday. For a past experience that did NOT happen, use 没……过: 我没去过北京。(Wǒ méi qù guo Běijīng.) — I have never been to Beijing.

A Chinese question uses ONE question device. ✗ 你是不是老师吗？(A-not-A plus 吗) → ✓ 你是不是老师？or 你是老师吗？✗ 你想吃什么吗？(a question word already asks it) → ✓ 你想吃什么？The rule: 吗 attaches only to a plain statement. If the sentence already asks — through A-not-A (去不去) or a question word (什么, 哪儿) — do not also add 吗.

A Chinese question word stays exactly where the answer would go; it does NOT move to the front as in English who / what / where. ✗ 什么你想吃？→ ✓ 你想吃什么？(Nǐ xiǎng chī shénme?) — What do you want to eat? English "Where do you live?" maps to 你住在哪儿？(Nǐ zhù zài nǎr?) — 哪儿 after 在, not 哪儿你住. Put the question word in the answer slot and leave it there.

Three words translate can but split the meaning. 会 (huì) = a LEARNED skill: 我会游泳。(Wǒ huì yóuyǒng.) — I can swim. 能 (néng) = capacity or possibility in the circumstances. 可以 (kěyǐ) = PERMISSION: 这里可以拍照吗？(Zhèlǐ kěyǐ pāizhào ma?) The key case: a skill you have but cannot use today is 会 but 不能: 我会开车，可是今天不能开。(Wǒ huì kāichē, kěshì jīntiān bù néng kāi.)

吗 makes ONE kind of question: a yes/no question on a statement (你是学生吗？). Do NOT add it to other types. ✗ 你去不去吗？(去不去 already asks) → ✓ 你去不去？✗ 你想吃什么吗？(什么 already asks) → ✓ 你想吃什么？Also, a question word does NOT move to the front like English; it stays where the answer belongs: 你住在哪儿？(Nǐ zhù zài nǎr?), not 哪儿你住. Choose ONE device, keep the word in situ.