Trick question

[firefly]

How do Romeo and Juliet communicate?

[spiff]

Phonetically?

[omblod]

By radio?

[Cetti]

I will agree with spiff and omblod and say over the airwaves.

http://www.dbfenterprisesllc.com/Information/phone
tic_alphabet.htm

[Magnum95]

they do not communicate because they don't really exist

[firefly]

I'm not sure that 'phoentically' is the same as radio, or cb radio, which is the right answer. Romeo would be call sign for someone whose name began with R, Juliet for J.