If you "foot" the bill, you pay it. To "foot" is an old way of saying "to total up" because the foot is at the bottom, and the foot of a bill, or total, is also at the bottom.
It is a way of saying that what you gave out, you're getting back; the roles have been reversed
Don't take an action that will result in harm to yourself that you did not intend.
to "foot the bill" originally meant to dispose of the charge for something by secreting the actual bill in one's shoe and walking out of the establishment without paying. The term evolved to its current usage of kicking the person who presents a statement of charges and leaving before he has a chance to recover.
It is a way of saying that what you gave out, you're getting back; the roles have been reversed
It means to accept all charges and pay the bill. Example: "I need to take the dog to the vet to get fixed, but who will foot the bill since I am too broke to pay?"
The phrase "one foot in the grave" is a idiom that means someone is very close to death or in a very weak or vulnerable state, usually due to age or illness.
It can be. It can also be a literal command to place one foot in front of the other and walk forward. As an idiom, it means to take small steps in order to reach a goal.
It's not really an idiom. It means "what are you thinking about."
It is not an idiom, it means your nose is itching.
RFP is not an idiom. It's an abbreviation.
"Sieve" is not an idiom. See the related link.