opportunist

機會主義者、投機者、投機取巧的人貶義

He is an opportunist who changes sides whenever it suits him.

他是個機會主義者，只要對自己有利就換邊站。

善於把握機會的人多用於運動報導

The striker is a natural opportunist in front of goal.

這名前鋒在門前總能把握住機會。

投機的、機會主義的貶義

Critics called the policy an opportunist move before the election.

批評者稱這項政策是選前的投機之舉。

伺機而動的、臨時起意的多指犯罪

Police believe it was an opportunist theft, not a planned one.

警方認為那是臨時起意的竊案，而非事先計畫。