The shì . . . de 是 . . . 的 pattern for past t - Cchatty

The shì . . . de 是 . . . 的 pattern for past tense actions Use the shì . . . de 是 . . . 的 pattern to emphasize when, how, or where something happened IN THE PAST, or who did it:

I came yesterday (not today).
Wǒ shì zuótiān lái de.
我是昨天来的。

I came by boat (not by plane).
Wǒ shì zuò chuán lái de.
我是坐船来的。

I was born in Beijing.
Wǒ shì zài Běijīng chūshēng de.
我是在北京出生的。

It was I who did it (not someone else).
Nà shì wǒ zuò de.
那是我做的。