why we say "combien *de* minutes?" and not "combien *des* minutes?"
You, are both right. "Combien (de)" is an example of a quantitative adverb. There are other examples of these, some where we know there will be more than one - "beaucoup (de)", for instance, but "de" is still always* singular in this form. Here are some others: un nombre (de) - a number of; peu (de) - few; moins (de) - fewer; tant (de) - so much/many; autant (de) - as much/many; encore (de) / plus (de) - more; trop (de) - too many.
- See this article for an exception - http://french.about.com/od/mistakes/a/beaucoupdes.htm
@siebolt - I'm not the best person to ask questions about grammar, but my understanding is as follows. Consider the sentence "Tu bois beaucoup trop de café sucré." (You drink far to much sugary coffee.)
Tu - subject pronoun
bois - verb
café - object noun
sucré - adjective - modifies the noun, making it sweeter.
Leaving us with beaucoup, trop (de). Clearly these are not nouns or verbs - and they are not adjectives, because they do not alter the properties of the object noun café. So they fall into the general "catch-all" of adverbs. Adverbs can modify verbs or other adverbs. So again, I think this makes sense:
trop (adverb) modifies the verb boire - "Tu bois trop." is a perfectly valid sentence without the noun café.
beaucoup (adverb) modifies the adverb trop - not just too much, but far too much.
Just to add to the above, "combien de minutes" is not a sentence, so it may be confusing as to the role that "combien" is playing. In a full sentence like: "J'ai combien [de minutes avant le départ]?" it is perhaps easier to see that the adverb combien is modifying the verb avoir, ("I have how many"... ? )
@ 1km: "much" and "many" are "non determining counting words" (sorry for the clumsy description, I just don't know the English terms) in Dutch. In German they are the same and treated like articles (viel Geld, viele Menschen). "Too much" to me is not necessarily belonging to the verb I have too much work. Of course languages do not work in the same way, look at "He is bigger than me" where the "me" in both Dutch and German has to be "I". Apart from the preceding, I am starting to think, that "trop" belongs to both the verb and the noun, which is a much discussed figure in Dutch grammar. In your example I would consider "beaucoup" an adjective used as an adverb, a quite common figure. Besides it is not an example of "beaucoup de". Nice writing to you. Bob
@ siebolt - I told you I was rubbish at grammar! "My Collins Robert dictionary says Fr. "beaucoup de" translates to Eng. "many" and is an adverb. But Eng. "many" translates to Fr. "beaucoup de" and is an adjective. I only mention this because it suggests you cannot infer across languages what part of a sentence any word becomes. (Elsewhere, I've been having a long debate about Fr. verbs prefixed with "le" becoming nouns - e.g."manger" and "le manger".) Regards, David