We've laid in a good supply of food for the winter.

我们存了足够的食物过冬

　　词组lay in，意思是store away for future use; provide; save，即，贮藏；贮存。
　　再如:
　　Every time they came to land, they laid in a good plenty of fresh water.
　　他们每次靠岸都要备足淡水。