The following is coming from the perspective of a native German speaker.

As far as I understand English grammar, most constructions are strictly right-associative:

>Why (is (this flower (not (on (the table))))), but on the floor?

>Why (is (not (this flower (on (the table))))), but the other one?

It wasn't always this way. If you look at *old* English literature and poetry, the grammar shared a closer affinity with the German language, where the "not" is more flexibly positioned. (The "not" is left-associative in German, but not in the whole sentence.) In German, the important part of a sentence is always at the beginning, where the interrogative pronoun is placed.

For example, if the following question is asked: 

>Where must this stay?/ Where has this to stay?

Then one might answer: 

>Here / Not here … must this stay! / has this to stay!

This does sound OK, or at least not too odd in German, but I believe that this sounds really strange for native English speakers.

The position of the word "not" can be a bit flexible in newer English language, as in the above sentence, but modern English usage allows this flexibility less.

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Please correct me, if I'm wrong. (Or if my English is wrong.)