은 그의

as for [something], his

→ 은
phrase Rare #16,458
as for [something], his 은 is a topic marker attached to the preceding noun, and 그의 means “his.” The term 은 그의 is not normally used by itself; it appears when a noun ending in 은 is followed by 그의, as in 돈은 그의 것이었다 (“The money was his”).
KO: 돈은 그의 것이었다.
EN: The money was his.

은 그의 결정에 후회하지 않는다고 말했다.

Tom said he didn't regret his decision.