He is viewing that situation as a serious problem.

He views that situation as a problem.

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

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

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

No problem, I will do that job.

That proposal is completely unthinkable.

As a practical question, how are we going to fund this project?

His nature is very kind.

Detailed information is needed to understand the nature of that project.