food既是可数名词又是不可数名词。仅仅指\"食物、食品\"的时候是不可数名词。强调食物的种类时就是可数名词。
food
n.食物;(某种)食物
复数 foods
They are at the end of their food supply.
他们的食物储备已消耗殆尽。
Whether we need more food depends on how many people turn up.
我们是否需要更多的食物，这要视到场人数而定。
Within three days they had exhausted their supply of food.
他们在三天之内就把所有粮食吃光了。
