を終わらせた

ended; finished

→ を
phrase Uncommon #11,601
ended; finished The past-tense form of を終わらせる, used when someone has ended or finished something. The を marks what was ended or finished.
JA: 彼は長い会議を終わらせた。
EN: He ended the long meeting.

彼女の仲裁私たちの口論を終わらせた

Her mediation ended our argument.

彼は講義を終わらせた

He finished the lecture.

ついに私は仕事を終わらせた

I finally finished my work.

土壇場になる前にこのプロジェクトを終わらせたほうがいい

We should finish this project before it comes down to the wire.