To "boil down" is to reduce the amount of liquid by boiling.
"Boils down to" is a way of saying the most important thing.
It all boils down to money.
When the boiling liquid in a pan flows over the edge, it has "boiled over".
If a situation "boils over", it gets out of control.
The argument boiled over into a fight.
Watch the video to learn more.
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