Watermelons, Tomatos, Pumpkins are Fruits or Vegetables ?

The confusion about fruit and vegetable is because of the botanical and culinary (cooking) terms.
Vegetable has no scientific definition. Vegetable can be defined as all parts of herbaceous plant eaten as food by humans, whole or in part.
or
A plant cultivated for an edible part, such as the leaves (lettuce), stems (asparagus), roots (carrots), flowers (broccoli), bulbs (garlic), seeds (peas).
Fruit is defined as any fleshy material covering a seed or seeds.
According to this definition pumpkin , pepper, tomato, capsicum, cucumber, squash, eggplant, and zucchini are all fruits because they all have seed but speaking in culinary (cooking) terms, they are all vegetables.
Simply, they are all grown as vegetables but the part eaten is botanically a fruit.