stock upvi phrasalphrasal verb, intransitive: Verb with adverb(s) or preposition(s), having special meaning and not taking direct object--for example, "make up" [=reconcile]: "After they fought, they made up."
(buy a lot of [sth] for future use)
储备 chǔ bèi
备足 bèi zú
We're low on batteries and canned goods; it would be a good idea to stock up before the storm.