When to use only "de" instead of "du, de la, des"

[Ray]

Bonjour, je sais qu'on peut dire "faire du ski", et du=de+le, mais quelquefois comme "il n'y a pas de", on doit seulement utiliser "de". Y a-t-il des autres moments qu'on doit seulement utiliser "de"?

Aussi, je pratique mon francais. Alors, peut-etre il y a des fautes de grammaire...j'aimerais si vous repondez en anglais. Merci!

[Neil Coffey]

In general, use du/de la/des will get replaced with a simple de in these cases:

(a) after a negated verb;

(b) where logically you would expect de du, de de la, de des -- i.e. where you would expect the preposition de followed de as an article, or in other words where you're effectively saying "of some...";

(c) in formal/emphatic use, des is sometimes replaced by de directly before a plural adjective, particularly when the adjective and following noun don't go closely together to form a set phrase (e.g. des beaux garçons would become de beaux garçons). When this actually happens is quite a complex issue; you probably don't need to worry about this terribly much for now...!

So (a) accounts for your il n'y a pas de..., and indeed other examples with negated verbs, such as:

Je n'ai pas de lait

Je ne mange pas/jamais de légumes.

The main exception is with c'est (and ce sont, c'était etc):

Ce n'est pas du beurre. = "It's not butter"

As an example of (b), consider the following:

J'ai besoin de ce pain. "I need this bread"

Une bouteille de ce vin. "A bottle of this wine"

Now, on the basis of these examples, you might expect the following to be logically possible:

*J'ai besoin de du pain. "I need some bread"

*Une bouteille de du vin. "A bottle of (some) wine"

but it turns out that speakers would actually say:

J'ai besoin de pain. "I need some bread"

Une bouteille de vin. "A bottle of (some) wine"

What happens is that the second de (and the word combined with it) effectively gets deleted.

[Neil Coffey]

I should also say that you'll find a few other exceptions to (a). But if you're just starting out, you can assume that "de" is generally used after negatives and look out for the exceptions...

[Cavin Graves]

Why isn't it "ce n'est pas de pain?"

[Neil Coffey]

Well, the slightly glib answer is "because it isn't". It just turns out that with the negative of c'est, c'était etc (and actually, to a large extent at least, with être more generally), French speakers don't use de in this way, but rather keep un, du, de la etc.

In fact, this extends a bit more generally to other verbs where you're "equating" one thing with another. For example, consider:

Ces règles ne sont pas devenues ____ normes.

Cela ne constitue pas ___ grand risque pour la santé.

Applying our rule (and given that it generally applies to un/une, not just to du/de la /des), you might expect de to be the only option to fill the gaps in these sentences. But in fact, des is probably more common in the first case, and un is at least equally possible in the second.

In general, the rule tends not to apply when you aren't simply negating the entire concept expressed by the sentence, but rather when the negation is 'qualified' in some way. Notice how in such cases, it often sounds strange to use "any" in English. So for example, consider the following:

Je n'ai pas acheté de pommes.

I didn't buy any apples.

Je n'ai pas acheté des pommes vertes (mais des pommes rouges).

I didn't buy green apples (but red ones).

Notice how in English you wouldn't say: *I didn't buy any green apples but red ones.

So... maybe the underlying reason for "Ce n'est pas du pain" and other similar examples has partly to do with the fact that there's an implicit qualification: "Ce n'est pas du pain, mais du...". But whether you try to find a "reason" or not, at the end of the day what matters is that that's what French speakers say... :)

[Cavin Graves]

Merci de votre réponse!

It is true that sometimes there just isn't a logical reason for such things but still answers such as yours do help (even if not logical, at least there is some sort of rule which "triggers" such phenomena).

Thanks again! :)