Format question for playwrights: I'm writing a musical and I was wondering how songs work

Question

I understand that lyrics are similar to dialog, but let's say I have two people singing at the same time. Would I write "BEN & RISA" in the Character element, or would I just use the same line twice in dual dialog/side by side dialog?

It's only two people otherwise id write the character as "BOYS," "GIRLS" or "COMPANY" or something

Answer 1

No I suppose you just write  , Ben & Risa. No sense in writing separately.

Besides , I don't see how lyrics are similar to dialog ? A lyric may be sung in the back-ground without  the active presence of anybody on the stage. A dialog necessitates two persons.