We should ponder over this.

这不能不引起我们的深思。

Give me a few days to ponder over it.

给我几天时间好好考虑这个问题。

Let me calm down and ponder over it carefully.

请让我静下心来仔细地思考一下吧。

I always ponder over how to make less mistakes.

我一直在思考如何才能少犯错误。

This is the problem that we should ponder over.

这是我们要思考的问题。