Because they want to cherish time.

因为他们想珍惜时间。

Cherish time can make life more valuable.

珍惜时间可以使生命变的更有价值。

Time is valuable, we should cherish time.

时间是宝贵的，我们应该珍惜时间。

We should learn how to cherish time and use it efficiently.

我们该学习如何珍惜时间且有效率的利用它。

I hope you will cherish time, study hard and growth healthily.

我希望各位同学珍惜时光，勤奋学习，健康成长。