For convenience, let's discuss this issue later.

We started a discussion about an important issue.

We discussed the issue.

Can you answer this question?

There are many arguments arising from diverse opinions about that issue, and no conclusion has been reached.

A new approach is needed to solve this set of problems.

The main problem with this project is the lack of communication.

This question text is too difficult, it's hard to understand.

This exam is a matter of life or death for me.

He is viewing that situation as a serious problem.