La comida y los verbos regulares..
Why in the sentence "She eats watermelon" does not have "A" between "EAT and Watermelon"....
2 Answers
'A' watermelon would refer to one specific watermelon that she was eating but 'she eats watermelon' means that generally she eats watermelon' a number of different watermelons on a number of different occasions.
As Kiwi says, but also: She eats a watermelon means she eats all of that watermelon, it's specific.
She ate a watermelon just before she fell ill. ( Here she ate the whole watermelon)
She ate watermelon and icecream, before she started to feel sick. ( Here we just know she ate an unknown amount of watermelon).