You think someone coarser than you is "crude", and someone higher class than you to be "putting on airs".

She is prudish.

He likes to posture as an intellectual.

He set up for learning.

I don't like his holier-than-thou attitude.

I can't stand those goody-goody types.

The mayor is a stuffed shirt.

An architect should not pretend to be an artist.

Why are you feigning innocence?!

When I was young, I was a bit scruffy and there were times when I didn't take a bath for up to two weeks during the summer.

You're so bossy.

He acts like a tough guy.