做宣传的作用是要吸引更多客人关注。

Zuò xuānchuán de zuòyòng shì yào xīyǐn gèng duō kèrén guānzhù.

The intent of advertising is to attract customers attention.

这个药的作用是让你睡得更好。

Zhège yào de zuòyòng shì ràng nǐ shuì de gèng hǎo.

The effect of this medicine is to help you sleep better.

老师的话对我起了很大的作用。

Lǎoshī de huà duì wǒ qǐ le hěn dà de zuòyòng.

The teacher’s words had a big effect on me.