What is the difference between "nothing but", "anything but", and "everything but"?

What is the difference between these phrases? When is it valid to use which? Should they be avoided as being ambiguous?

Solution 1:

Nothing but A

Means only A. You don't want anything else.

Anything but A

Means that you don't want A. You could have B or C, or maybe even both B and C (and even E if someone offers) - but NOT A!

Everything but A

Means that A is the only thing you don't want. You do want the rest of the entire alphabet - but NOT A!

Solution 2:

"Nothing but" means only:

• Nothing but the best.
• Only the best.

"Anything but" means any one thing except whatever follows but:

• Don't make me go to school. Anything but that.
• Don't make me go to school. You can make me do anything else, but don't make me go to school.

"Everything but" means everything excepting whatever follows but:

• He remembered to bring everything but his toothbrush.
• He brought everything with him except his toothbrush, which he left behind.

Solution 3:

But here means except.

I want nothing but chocolate

means I do not want to have any food except chocolate.

Give me anything but chocolate

means I can eat all kinds of food except chocolate.

I will eat everything but the chocolate

means I am going to have all the food in front of me except the chocolate.