"What city do you live (in)?"
Below is another example of "What city do you live in?"
Note that in this second example I'm doing a bit of a twisting movement on the sign CITY.
The twisting movement doesn't change the meaning of the sign one bit (in this example).
I think it just makes some signers sleep better at night knowing they use a "twisty" movement.
You know the type. They can't appreciate something if they haven't sweated for it.