你在吃饭的时候，请不要说话。

Nǐ zài chīfàn de shíhou, qǐng búyào shuōhuà.

While you're eating, please don't talk.

我喜欢吃早饭的时候喝咖啡。

Wǒ xǐhuān chī zǎofàn de shíhou hē kāfēi.

I like drinking coffee when I eat breakfast.