A + 是 + B
Reach for this from day one — it is the basic definition pattern in Chinese. A 是 B says 'A is B,' where A is the thing you are defining and B is the category, identity, or definition. Use it to introduce people (他是老师), assign categories (苹果是水果), and equate concepts (自私是爱自己). The verb 是 does not change form for tense or number; the same word covers 'am, is, are.'
Structure
[A (noun/topic)] 是 [B (noun/definition)]。
shì
How to Think About It
是 is an equals sign, not an action verb. It links two NOUN-like things and tells the listener they refer to the same entity or category. Because 是 already means 'is,' you do NOT use it with adjectives in everyday Chinese — 天气是冷 sounds wrong; native speakers say 天气很冷. Save 是 for noun-to-noun links and for the 是…的 frame that emphasizes a feature.
Examples
他是老师。
Tā shì lǎoshī.
He is a teacher.
苹果是水果。
Píngguǒ shì shuǐguǒ.
Apples are fruit.
中文是一门语言。
Zhōngwén shì yī mén yǔyán.
Chinese is a language.
Common Mistake
Learners use 是 before adjectives, copying English 'is.' Chinese adjectives behave like stative verbs and stand alone, usually with 很 instead of 是.
他是高。
他很高。
Don't Confuse With
Subject + 是 + ... 的
Adds 的 to spotlight a feature like color, origin, or material (苹果是红的). Plain A 是 B equates two nouns or categories.
Subject + Adjective (no 是)
For everyday descriptions, drop 是 (他很高, 天气不错). Use 是 only when the predicate is a noun.
Subject + 叫 + Name
For names of people or things, Chinese prefers 叫 (我叫小明). 是 also works for names but feels more formal — 'I am called X' vs 'My name is X.'
Practice
Fill in the blank: 我 ___ 学生。
Show answer
是
Fill in the category: 狗是 ___（animal）。
Show answer
动物
Arrange into a sentence: 中国人 / 是 / 我
Show answer
我是中国人。
Translate to Chinese: She is a doctor.
Show answer
她是医生。
Write one definition sentence using A 是 B.
Show answer
数学是一门很重要的学科。
Hear It in Real Episodes
This pattern appears in 1 Fluentide episode:
Related Grammar Patterns
Acquire by listening
Hear A + 是 + B in real Chinese, not in a textbook.
Fluentide picks the next news episode at your level, so this pattern shows up again and again in real context. The transcript marks it, the audio drills it. Free to start, no card.