他在公司危机时迅速接管了领导职位，证明了自己是个善于把握机会的人。

He quickly took over the leadership position during the company crisis, proving to be a real ___opportunist.

他在公司危机时刻突然提出加薪要求，真是个投机分子。

He suddenly asked for a raise during the company crisis, showing his ___opportunistic behavior.