This is not an idiom. It means exactly what it seems to mean - there are not many left of whatever you're referring to.
It made me laugh very much.
"To be" is not an idiom - it's a verb.
This is a slang term meaning that something cost much less than it should have.
it means 'too much', 'more than is necessary', 'overkill'
In short supply means that there is not much of whatever it is.
This is not an idiom. It means exactly what it says. The gladness he felt in the Spring left his heart. He was feeling sad.
Yes, you can change an idiom with your own words, but it may lose its original meaning or impact. Idioms are commonly used phrases in a particular language that have a figurative meaning. Modifying them may result in confusion or a loss of the intended message.
Pest is not an idiom. It's a word.
The idiom "apple shiner" means the teacher's pet.
The meaning of the idiom in the pink of health means being in good health.
This is not an idiom. It means just what it says. Temper: the personality and state of mind Genius: a person much more intelligent than the average
The idiom means impress someone is egg on