The green examples should break at all their hyphens; the red ones should not.

T-shirt

billy-o

tally-ho

co-author

hi-de-hi

far-sighted

hocus-pocus

Nanki-Poo

Miami-Dade

Wells-next-the-Sea

Lee-on-the-Solent

\\/^-_-^\//

(''')-.-(''')

:-">

<{^-^}>

:-D