"European vegetables are good."
Translation:Les légumes européens sont bons.
If I wanted to say "the rice", I would say "le riz", but if I just wanted to say "rice" I could say "du riz", and "des" is the plural of "du", which I think you say if you don't want to use "the" before a noun, and there is no "the" in the sentence, so shouldn't "des" be the right answer as opposed to "les"?
As a general rule, English spares articles while French does not.
In many cases, you cannot directly translate an article or a non-article from English to French.
The only way to pick the right article in French is to understand what is meant
the rice is good (specific) = le riz est bon (definite article)
a good rice was served (indefinite) = un bon riz a été servi (indefinite article)
(some) vegetables were served = des légumes ont été servis (plural indefinite article)
rice is good for you (generality) = le riz est bon pour vous (definite article)
I eat (some) rice (partitive) = je mange du riz (partitive)
I love rice (in general) = j'aime le rix (definite article with all appreciation verbs: aimer, préférer, adorer, détester, apprécier, haïr)
Not really, but I'm sure you know this now (posting here for the benefit of new learners). "Des légumes" only refers to an undetermined amount of vegetables, not vegetables in general or a certain bunch of vegetables. To speak of vegetables in general, it must be "les légumes". If you wanted to say "some vegetables" (not all vegetables), it would be "certains légumes sont bons".
First, légumes is masculine, so it has to be "bons" instead of "bonnes". Second, you need the definite article in French even if it isn't necessary in English. In English you can say "I like dogs". You can't say "J'aime chiens" in French. It would have to be "J'aime les chiens". If you think it's confusing, imagine a French native learning English and wondering where all our definite articles disappeared to! Hope that helps!
"European vegetables are good" means that all of them are. It is a blanket statement and the whole category of "European vegetables" in general is concerned.
In French, generalities need a definite article.
"Des" is the plural of "un/une". The meaning of "des légumes" is "more than one vegetable", not "all vegetables in general".