English Translation
That’s MY line!
“那是我该说的话!” translates to “That’s what I should say!” in English.
Is what the explanation from ChatGPT says.
As someone who’s friends with native Chinese speakers, I also think 那是我该说的话！ Should mean “That’s what I should have said!” instead of “That’s MY line”. It just sounds too…inauthentically translated compared to what ChatGPT and my experience with Chinese speakers tells me. 该, means should have, 说的话 basically means “said” so "那是我该说的话！” should basically mean “That’s what I should’ve said!” instead of “That’s MY line”.