ものにする
mononi suru

Suru Verb
Expression

1. to get; to secure; to take possession of; to make one's own; to win (someone's heart)

Usually Written in Kana
どんなに勉強 べんきょうしたって、1 いち ねん ねん外国 がいこく をものにすることはできない。
donnani benkyō shitatte ichinen'ya ninende gaikokugō mononi suru kotowa dekinai.
However hard one may work, one cannot master a foreign language in a year or two.
Suru Verb
Expression

2. to learn; to master

Usually Written in Kana
Suru Verb
Expression

3. to complete

Usually Written in Kana