Answer
The ressonance structure should look like this:
Work Step by Step
1. Draw all lone pairs that are missing.
As we can see, the nitrogen atom had a lone pair that was not drawn.
2. Identify the lone pair next to the pi bond:
They are circled in red in the image. "Next" mean that, there is exactly one bond between the lone pair and the pi bond.
3. Draw the arrows:
Follow the same pattern we have learned in the chapter.
(Bring down the lone pair to the bond in the middle, and kick up the pi bond to form a lone pair.)
4. Do the changes based on the arrows.
* Don't forget the formal charges!
