「彼はわがままだから、一定の距離をおいて仕事をしたほうがいい」」
He is self-centered. You may want to keep your distance from him when you
have to work around each other.
わがまま：self-centered, narcissist
一定の距離：certain distance
「彼は責任感がなく、ぶつぶつ言って仕事をしない」
He is irresponsible at work and always complains.
「彼は責任がない」
He doesn’t take responsibility for his work.
日本 
