"Je mange la salade avec de l'huile."
Translation:I am eating the salad with some oil.
There's a difference between saying "THE salad" versus just saying "salad."
- I'm eating salad = Je mange de la salade
- I'm eating the salad = Je mange la salade
- I'm eating my salad = Je mange ma salade
- I'm eating a salad = Je mange une salade
Because French mostly requires modifiers for every noun, you can think of "de la" as a placeholder for a modifier if you don't need the modification.
Let's imagine that you made salad this morning and you put it in the fridge. Hours later, you see your friend eating something, and he says "I'm eating salad." Would you automatically assume that it's your salad? Perhaps he bought his own salad? Now what if he says "I'm eating the salad"? It should automatically be understood what salad he's eating.
For general statements about salads, you must use "la salade" as in "La salade est dégoutante" (Salad is disgusting.)
why is it de l'huile instead of du huile? Just because oil begins with an h?
It's incorrect because it should be THE salad instead of just 'salad'. If it says 'la salade' then it means THE salad; if it says 'de la salade' then it translates to some salad and its okay to leave it as 'salad with oil'. In this example it's 'la salade' so you have to write 'the'.
Hope this helps ^-^
I am = Je suis; I am eating = Je mange. Je mange can be translated in more than one way: I am eating, or, I eat.