It is impossible to be sure about the value of land.

要确定土地的价值是不可能的

I'm sorry, but I can't be sure about that.

不能保证会是这么个结果…但我会尽力做。

You can be sure about their interest in it.

你可以肯定他们对引很感兴趣。

Be sure about the purpose of writing the feature story.

确定好写特写的目的。

That is scary, and we cannot be sure about changes in the future.

这是可怕的，因为我们无法确定未来会发生什么变化。

The business stakeholders will not be sure about some requirements.

业务利益干系人将无法确定某些要求。