Honesty is the best policy.

诚实为上策。

Where there is a will, there is a way.

有志者，事竟成。

Time is money.

时间就是金钱。

Don't waste time. Time is life.

不要浪费时间。时间是生命。

Learn while you play.

边玩边学。

Keep your face to the sunshine and you cannot see a shadow.

面对阳光，就不会看到阴影。

Keep your words sweet and your thoughts honest.

要甜言蜜语，要心怀坦荡。

Every cloud has a silver lining.

每朵乌云都有银边。

Small seeds grow into big trees.

小种子会长成大树。

You can't make an omelette without breaking a few eggs.

不打破几个鸡蛋，你就做不成煎蛋卷。

这些格言简洁明了，适合四年级学生学习和记忆。