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fellow; guy; chap
thing; object
he; she; him; her
あいつは昔から約束を守らないやつだった。
That guy has never been one to keep his promises.
隣のやつがまた夜遅くまで騒いでいた。
The guy next door was making noise late into the night again.
あのやつには何度言っても同じ失敗を繰り返す。
No matter how many times you tell that fellow, he repeats the same mistake.