The mistakes that actually cost you

01✗我是累。

✓我很累。

Why：是 only links nouns. Adjectives behave like verbs, so the neutral copula is 很 — and here 很 does not mean 'very'.

02✗我不有。

✓我没有。

Why：有 is always negated with 没. 不 is for present, future, habits and modals; 没 is for past and for having.

03✗我没知道。

✓我不知道。

Why：Knowing is a state, not an event, so 不. 没 would mean 'I didn't find out'.

04✗两书

✓两本书

Why：Chinese requires a measure word whenever a number meets a noun. The default is 个, but real nouns want real classifiers.

05✗我买了一只鞋。

✓我买了一双鞋。

Why：Things that come in pairs take 双, not 只. 只 means 'one of the pair'.

06✗我看电影昨天。

✓我昨天看电影。

Why：Time expressions precede the verb. This is the number one word-order error from English.

07✗我学习汉语在中国。

✓我在中国学习汉语。

Why：Place phrases are prepositional and sit before the verb. English puts them after the object.

08✗他比我很高。

✓他比我高。

Why：比 constructions do not accept 很 / 非常 / 太.

09✗你去或者不去?

✓你去还是不去?

Why：或者 is for statements; 还是 is for questions. English 'or' covers both, which is exactly the trap.

10✗我吃和喝。

✓我又吃又喝。

Why：和 joins nouns only. Verbs take 又…又… or 也, and clauses take 然后.

11✗我游泳得很好。

✓我游泳游得很好。

Why：Degree complements repeat the verb. English has no equivalent structure at all, so this must be learned as a pattern.

12✗我学习汉语两年。

✓我学了两年汉语。

Why：Duration goes after the verb and usually needs 了. The object can follow the duration phrase.