French fries is not a healthy food 为什么要加a这个不定冠词?

Question

如题所述

Answer 1

French
fries
is
not
a
healthy
food.这种加不加
a
都能说通的；meat
and
fish
are
healthy
food.里面由于主语是“meat
and
fish”所以要么food表示食品，要么表示种类用foods。