“Good thing I have my warm coat.”
Good thing … is a conversational shortening of It's a good thing (that) …, expressing relief or satisfaction. Tina is glad she has her warm coat.
A1-26 / CEFR A1 / EPISODE 26
Lending a coat
SceneOn a cold day.

WORDS & CONTEXT
Good thing … is a conversational shortening of It's a good thing (that) …, expressing relief or satisfaction. Tina is glad she has her warm coat.
Brave usually describes courage, but applied to a color it suggests a bold choice. Tina playfully encourages Frank to wear pink by presenting it as a color that takes courage.