父は以前は煙草を吸っていたけれど今は吸いません。

。

My father used to smoke, but he doesn't anymore.

Literal

Father [topic-は] previously [contrast-は] tobacco [object-を] was-smoking [but-けれど] now [contrast-は] does-not-smoke [polite-ません].

Two contrastive は markers frame the before/after: 以前は ('previously' — contrasted with now) and 今は ('now' — contrasted with before). けれど is a slightly more formal variant of けど.