その問題について彼らと討論しよう。

that (something or someone distant from the speaker, close to the listener; actions of the listener, or ideas expressed or understood by the listener); the; um...; er...; uh...

question (e.g. on a test); problem; problem (e.g. societal, political); question; issue; subject (e.g. of research); case; matter; question (i.e. doubt); public discussion; controversy; trouble; problem; inconvenience; difficulty

concerning; regarding; per (e.g. 100 yen per person); for every

they (usually male); them

if; when; and; with; particle used for quoting (with speech, thoughts, etc.); quoting particle; promoted pawn; indicates question (sentence end)

debate; discussion