english one minute:keep one'snose to the grindstone是什么意思

keep one'snose to the grindstone是什么意思 请问keep up one's mind+? "Keep one's saw sharp"是什么意思 why don't you make a fire____warm? A .keep B .to keep That child can't keep still for a moment. Don't keep thinking about it.(是什么意思) DON'T KEEP STH FROM ME是什么意思 one thing I can't forgot we can't keep amending orders to FPI这句话如何理解? i don't want that sort of thing ___ (keep) happening.