Do not criticize others if you are not prepared to be criticized in return

(simile, idiomatic) To look very satisfied and happy.

Alternative form of that ship has sailed

Alternative form of that train has left the station

That opportunity has already passed; that cannot be undone.

When you use a thing too much, it ultimately breaks down at some point.

Indicates approval at someone who is doing something praiseworthy.

plural of straw that stirs the drink

(idiomatic) Said of something that has an even greater impact or effect than what is readily apparent, considering the context.

Synonym of that dog won't hunt.