That proposal is completely unthinkable.

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

He tied the rope to the tree.

He is training to strengthen the tightening of his muscles.

He tightened his fists in tension.

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

We have to brace ourselves for the upcoming difficulties.

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.