I will lose _________ before an examination because of much worry.

It is important to have your eyes examined regularly to check for any sign of eye disease that may not have any __________.

—Some people believe that robots will take over the world one day.—What if that is the ________?

The old man gave ______ on behalf of an accused person.

In my opinion, you can widen the _____ of these improvements through your active participation.