Introduction
Once both speakers know that something happened, 是……的 (shì … de) puts the spotlight on one detail of it — when, where, how, or with whom. 我是昨天来的。(Wǒ shì zuótiān lái de.) — It was yesterday that I came. The coming is old news; the day is the point.
Overview
Structure: Subj. + 是 (shì) + [emphasised detail] + Verb + 的 (de)
| Pattern | Example | Translation |
|---|---|---|
| 是 + Time + V + 的 | 我是昨天来的。(Wǒ shì zuótiān lái de.) | It was yesterday that I came. |
| 是 + Place + V + 的 | 我是在北京学的。(Wǒ shì zài Běijīng xué de.) | I learned it in Beijing. |
| 是 + Means + V + 的 | 我是坐飞机来的。(Wǒ shì zuò fēijī lái de.) | I came by plane. |
| 是 + 跟 + Person + V + 的 | 我是跟朋友去的。(Wǒ shì gēn péngyou qù de.) | I went with a friend. |
| Question | 你是什么时候来的？(Nǐ shì shénme shíhou lái de?) | When did you come? |
是……的 (shì … de) is not the same as 了 (le):
- 我昨天来了。(Wǒ zuótiān lái le.) — I came yesterday. You are reporting the event.
- 我是昨天来的。(Wǒ shì zuótiān lái de.) — It was yesterday that I came. Everyone knows you came; you are supplying the when.
- 是 (shì) may be dropped, and often is: 我昨天来的。(Wǒ zuótiān lái de.) The 的 never goes.
- The negative keeps 是 (shì): 我不是昨天来的。(Wǒ bú shì zuótiān lái de.)
Examples
我是昨天来的。
Wǒ shì zuótiān lái de.
It was yesterday that I came.
你是什么时候来的？
Nǐ shì shénme shíhou lái de?
When did you come?
我是坐飞机来的。
Wǒ shì zuò fēijī lái de.
I came by plane.
他是在北京学的中文。
Tā shì zài Běijīng xué de Zhōngwén.
He learned his Chinese in Beijing.
这本书是我在书店买的。
Zhè běn shū shì wǒ zài shūdiàn mǎi de.
I bought this book at the bookshop.
我不是一个人去的，是跟朋友去的。
Wǒ bú shì yí ge rén qù de, shì gēn péngyou qù de.
I didn't go alone, I went with a friend.
Usage Notes
- This construction only works for things that have already happened. For the future, use an ordinary sentence.
- The detail being emphasised sits between 是 (shì) and the verb. Move it and you emphasise something else.
- With an object, the 的 (de) may come before it or after it: 他是在北京学的中文 (tā shì zài Běijīng xué de Zhōngwén) and 他是在北京学中文的 (tā shì zài Běijīng xué Zhōngwén de) are both correct.
- Do not use 了 (le) as well: ❌ 我是昨天来了的 (wǒ shì zuótiān lái le de).
- 是 (shì) is 4th tone, so 不 becomes bú in the negative — bú shì.