老师让我们用沙子做一个简单的实验。

Lǎoshī ràng wǒmen yòng shāzi zuò yí gè jiǎndān de shíyàn.

The teacher asked us to use sand to do a simple experiment.

这种玻璃是用很细的沙子做成的。

Zhè zhǒng bōli shì yòng hěn xì de shāzi zuòchéng de.

This kind of glass is made from very fine sand.

小孩子在海边用沙子堆城堡。

Xiǎoháizi zài hǎibiān yòng shāzi duī chéngbǎo.

The children are building a castle with sand by the sea.