Nouveau and neuf

Question

Tu as acheté un ________ véloWhy here we cannot use neuf, it is a new bike so it has not been used.Futhermore it is not living things, neuf here sounds make sense.

Maarten Kamp · Accepted Answer

Gene, 
Your reasoning on using ‘ neuf ‘ is correct in context, but the structure of the question makes ‘ neuf ‘ an incorrect choice here. The adjective ‘ neuf ‘ cannot be used before the noun, leaving ‘ nouveau ‘ as the answer here to fill the blank space before the noun. 
The relevant section of the lesson is 
 
          “ In some context, obviously, both are correct.
However, the main difference of usage is the position in the sentence:
- neuf is placed AFTER the noun- nouveau is placed BEFORE the noun “