Denshi Jisho — Online Japanese dictionary

為に ために 1: (Usually written using kana alone) for; for the sake of; to one's advantage; in favor of; in favour of; on behalf of;
2: because of; as a result of
Conjunction 
為にする ためにする to have an ulterior motive; to have an axe to grind
Expression, Suru verb - irregular 
為になる ためになる to be of benefit; to be useful; to be good for you
Expression, Godan verb with ru ending 
為に成る ためになる to be of benefit; to be useful; to be good for you
Expression, Godan verb with ru ending 

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