There is also another: to keep/put one's nose to the grindstone. It means to focus heavily on work, to be conscientious.
OMG, I will never remember them all, it seems every day ten new ones come into being. :(:( I am too old to learn them from the scratch and all my schools were hopeless about them, too, as I was only taught high English. BTW, I once took up perusing a dictionary of idioms during school breaks and gave up after a few days because it was getting impossible. :)
Just checked into Random, that mine of information:
Make a copy of this post so you can refer to it the next time you are tempted to double down again.mainly US to continue to do something in an even more determined way than before: Expect to see Fox double down on its marketing efforts to give the movie a big boost.
Instead of learning from his mistakes, he's doubling down.
really should know better than to mouth off in public,1. To speak without discretion; to speak too loudly or freely, especially about sensitive topics or information. We would have gotten away with our plan if your dumb cousin hadn't started mouthing off all over town.
2. To make disrespectful comments; to sass someone. You're going to get detention again if you keep mouthing off to your teacher.