The idiom "keep schtum" is used to tell someone to be quiet or to stop talking. It has a slightly harsh tone and is often used when the speaker wants someone to cease their chatter without being too confrontational. The literal meaning of the word "schtum" is "to shut up.

"Mind your own beeswax" is an idiomatic expression that means to mind one's own business or affairs, and not interfere with or meddle in the lives of others.

The idiom "best thing since sliced bread" is used to describe something that is considered an excellent new development or improvement. It can be used to praise a product, a service, or a person's performance. It indicates that the new thing is widely appreciated and has become popular.

The idiom "drive up the wall" means to become extremely angry or upset. It can also mean to be very stubborn or unwilling to change one's mind.

The idiom "a leopard can’t change its spots" means that someone cannot change their behavior or character just because they want to. It is a warning that people's true nature will eventually reveal itself, and it is not possible to hide who you really are forever.