food复数形式foods
n.食物;(某种)食物
foods=many kinds of food，表不同种类种类的食物时候可数
例句：
Many people dunk their foods in coffee, tea or milk.
很多人在咖啡、茶或牛奶里蘸东西吃。
Most foods that we eat are safe for birds.
我们食用的大多数食物对鸟类都无害。
