That's not correct. "brauchen" is a full verb as well as a modal.
in English, when you say ''you don't have to go'' what you mean actually is ''you don't need to go'' which is why you cannot use ''müssen'' and ''brauchen'' is a better choice; although, I've seen people use either of the two, and context make it clear what they mean: ''you must not ...'' vs. ''you don't have to ...''
"Du magst nicht zu gehen" is wrong. I guess you're trying to say "Du möchtest nicht gehen". In this case, the modal verb is "mögen". It expresses volition, or rather lack thereof.
"nicht brauchen" in "Du brauchst nicht zu gehen" expresses obligation, or rather lack thereof.
Ah ah! I wanted not to use a modal verb to give a counter example but I actually used one! I guess the correct statement of what I wanted to say was "Du magst ES nicht zu gehen" --> "You don't like to go". But in any case, it is indeed modal... Mm... I will have to wrap my mind around it. Thanks for answering! Ah!... I found a counter example: "Du versuchst nicht zu gehen". This is not modal. My point is: isn't "brauchen" (to need!) just a normal verb sometimes indeed expressing a form of modality, but should not be considered per se as a modal verb? The Wikipedia page (http://de.wikipedia.org/wiki/Modalverb) says: "Im umgangssprachlichen Gebrauch wird neuerdings auch das Verb „brauchen“ (in der Negation) mit der Bedeutung „müssen“ als Modalverb (d. h. mit Infinitiv ohne zu, es gibt dialektal sogar die Form er brauch) verwendet, dies gilt standardsprachlich jedoch als falsch."
"Du magst es nicht zu gehen" doesn't work either.
"You would use "mögen" and "gefallen" to describe whether you like objects or not. To explain what you like doing, simply add the adverb "gern(e)" after the verb denoting the action in question. If you don't like doing an action, add nicht gern(e)"
The Wikipedia article is a bit of a mess. In "Du brauchst nicht (zu) gehen", "brauchst nicht" is a modal verb regardless of whether you use "zu" or not. It's just that the version without "zu" is colloquial.
As far as "Du versuchst nicht zu gehen" goes, there is no modality implied in the first place. It is a catenative verb, but not a modal verb as trying is not a category of modality.
I'm confused by you saying that brauchen is a modal verb in your explanations. Everywhere I've seen so far seemed to suggest this is the exhaustive list of German modal verbs: wollen, sollon, müssen, mögen, können, and dürfen.
The explanation I understand from trying to wrap my head around this is pretty simple and explains it in terms of two type of constructions:
What I read suggested that the rule for constructing an infinitive clause doesn't involve simply bumping the infinitive verb to end and inflecting the other -- in contrast to the rule for modal verb constructions -- but also requires zu to precede the infinitive verb. The sentence we have here is an infinitive clause, since brauchen is not a modal verb. Is this explanation incorrect?
The reason why it's not listed on that website might be that it's not considered a core modal verb, it only functions as a modal if it's negated, and it occurs more often in spoken than in written German.
In other words, when we try to couple two verbs in an idea like "to need" and "to go", and the former is not a modal verb, our construction follows those rules of an infinitive clause. However, the former was a modal verb, we'd follow the usual modal verb construction rules and not have "zu" anywhere. See examples in the link I gave.
This structure is used only for negations.
To say "you need to go" you would NOT say:
- "Du brauchst gehen"
You would say:
- "Du musst gehen"
Also, "Du brauchst nicht (etwas zu tun)" and "Du musst nicht (etwas tun)" have the same meaning. That being "You don't have to".
Furthermore, to say "You must not" you would say:
- "Du darfst nicht (etwas tun)"
Colloquially you can leave out the "zu", but it's best to just leave it in, because some people insist upon it.
"Wer brauchen ohne zu gebraucht, braucht brauchen gar nicht zu gebrauchen!"
It's been a long time since I learned helper verbs (or modal verbs). Let me know if I have this right.
We have the "zu" here because "brauchst" in this case is like how we say "need to" in English. The "zu" doesn't really make up any part of the infinitive "gehen", but belongs as a necessary part of the verb "brauchst" right? Am I even close? :P
EDIT: Now that I've learned this rule, let me explain it. Only modal verbs like müssen, wollen, sollen, dürfen and a few more do not require the "zu". Those are just special words. Any other word like in this case "brauchen" needs "zu" if it belongs with a second verb. Furthermore, if that second verb fits the format of "in order to [adverbly] [verb]" use "um [adverb] zu [verb]"
The verb here is "gehen", not "zugehen". Otherwise, the sentence would be "Du brauchst nicht zuzugehen".
Here the "zu" is simply a preposition and not part of the verb, if it were a prefix, since it comes after a modal, it would be written without the space between "zu" and "gehen".
Also in this structure, we need the preposition "zu". When using "zu" with a separable prefix verb, the "zu" goes between the prefix and the verb stem. So, like stated above, it would be "zuzugehen".
zu (prefix) + zu (preposition) + gehen (verb stem) = zuzugehen
The verb "brauchen" in the context of "nicht brauchen, etwas zu tun" is a modal verb. (You may have learned that modals don't take the "zu + infinitive" construction, however, this is an exception.)
Now try substituting the verb "brauchen" with "müssen".
- Du brauchst nicht zu gehen - You don't have to go.
- Du musst nicht gehen - You don't have to go.
Now try this with any other modal.
- Du sollst nicht gehen - You're not suppose to go.
- Du darfst nicht gehen - You're not allowed to go.
- Du wirst nicht gehen - You will not go.
- Du willst nicht gehen - You do not want to go.
- Du möchtest nicht gehen - You would not like to go.
Notice where the "nicht" is placed in each sentence following a modal? It remains there in this case as well.
I hope this helps!
"Du musst gehen." <===============> "Du darfst nicht bleiben."
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| "Du kannst nicht bleiben."
"Du solltest (besser/lieber) gehen."
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| "Du solltest (besser/lieber) nicht bleiben."
"Du kannst gehen."
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| "Du musst nicht bleiben."
"Du darfst gehen."
"Du darfst bleiben."
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||| "Du musst nicht gehen."
"Du kannst bleiben."
||||||||||||||||||||||||||||||||||||||||||||||||||||||||| "Du solltest (besser/lieber) nicht gehen."
"Du solltest (besser/lieber) bleiben."
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||| "Du kannst nicht gehen."
"Du musst bleiben." <==============> "Du darfst nicht gehen."
That should be the whole range of expressions, from forcing someone to leave, to forcing someone to stay. The verb "können" here is not meant in the sense of "(to) be able to". It is rather used in the sense of "dürfen". Although there is a tiny, barely noticeable difference that makes "dürfen" a little more compelling than "können", it is often used synonymously.
on the left side are the 'positive' sentences (without "nicht") and on the right side the 'negative' sentences (with "nicht").