我看到他在偷笑。

Wǒ kàndào tā zài tōuxiào.

I saw him laugh in secret.

我的钱包被偷了！

Wǒ de qiánbāo bèi tōu le!

My wallet was stolen!

你在偷东西吗？

Nǐ zài tōu dōngxi ma?

Are you stealing things?