下句对吗？

正确的应该是
My favourite food is apple.

You can also say "Apple is my favourite fruit".

应该是：
My favourite food is apple. 或 My favourite food are apples.

The correct sentence should be:
My favourite food is apple.

Becasue apple in this sentence means a kind of fruits, not lots of apples. But when you talk about things you like, you may say:
I love cars/dogs....

apple后面不应该加s,以后可以倒过来检验一下对不对
apples is my favourate food.明显不对

应该是“IS APPLE”IS后加单数~！