Potatoes is my favorite food .中的系动词是is么?

问题描述:

Potatoes is my favorite food .中的系动词是is么?
那 Bananas is my favorite .对么 ,

Potatoes is my favorite food .中的系动词是is.不过这里要用are吧.
Bananas is my favorite .不对.Bananas是复数,谓语应用are.