The verb 是 (to be)

Structure A + 是 + B

是 (shì) links two nouns and states that one IS the other: "A is B" (identity, job, nationality…). IMPORTANT: 是 is NOT used with adjectives. You do not say 我是高 ("I am tall"); for that you use 很 + adjective (我很高). 是 only links a noun to a noun. Negate it with 不 → 不是.

Examples

我wǒ是shì学xué生shēng。
I am a student.
他tā是shì老lǎo师shī。
He is a teacher.
这zhè是shì我wǒ的de书shū。
This is my book.
我wǒ不bù是shì中zhōng国guó人rén。
I am not Chinese.

Levels are indicative: they follow the standard Chinese Grammar Wiki (AllSet Learning) progression, not an official HSK 3.0 mapping. We never assign levels by eye.

This point and the other 370, with audio on every example, inside Wanyu.