有空儿的时候，我喜欢看电影。

Yǒu kòngr de shíhou, wǒ xǐhuān kàn diànyǐng.

When I have free time, I like to watch movies.

有空儿的话，一起来我家吃饭吧。

Yǒu kòngr de huà, yìqǐ lái wǒjiā chīfàn ba.

If you are free, come to my home to eat together.

老师，您明天有空儿吗？我想问几个问题。

Lǎoshī, nín míngtiān yǒu kòngr ma? Wǒ xiǎng wèn jǐ gè wèntí.

Teacher, are you free tomorrow? I would like to ask a few questions.