To disguise, to change something's appearance, so that it can't be recognized.

He wasn't good at disguising himself, so we knew who he was right away.

She wore a disguise, so I wasn't sure who she was.

To clarify, to explain, or make something clear.

We weren't sure what he meant until he clarified his ideas.

Everyone was confused until she clarified what she meant.

To confuse, to make things difficult to understand, the opposite of to clarify.

Everyone was confused because her presentation was so disorganized.

He confuses people, because he keeps changing his ideas.

The instructions were confusing, so nobody knew what to do.

To ignore, to try not to notice or deal with something, to act as if something isn't there.

We tried to ignore her, but she finally stood up and told everyone to shut up.

People don't respect or like her, so they ignore her in the office.

(He is an ignorant old fool, so we should just ignore him.)

To confirm, to indicate that something is correct or completed as expected.

We weren't sure if he was going to accept our offer, until he called and confirmed it.

We can't start the project without written confirmation that we agree on the details.

(after the explosion people were confused and unsure about where to go.)