Word: 万一 (wànyī)

万一下雨，我就不去。

Wànyī xiàyǔ, wǒ jiù bú qù.

In case it rains, I won't go.

万一你生病了，吃这个药。

Wànyī nǐ shēngbìng le, chī zhège yào.

Take this medicine in case you get sick.

万一发生火灾，按下按钮。

Wànyī fāshēng huǒzāi, àn xià ànniǔ.

In case of fire, push the button.

万一我来晚的话，就别等我了。

Wànyī wǒ lái wǎn dehuà, jiù bié děng wǒ le.

Should I be late, don't wait for me.

万一我来晚的话，请不要等我。

Wànyī wǒ lái wǎn dehuà, qǐng búyào děng wǒ.

If by any chance I arrive late, please don't wait for me.

万一来不了，我会先给你打电话。

Wànyī lái bù liǎo, wǒ huì xiān gěi nǐ dǎdiànhuà.

In case I can't come, I'll give you a call beforehand.