A man pointed a gun at them and pulled the trigger.
一个男人用枪指着他们，扣动了扳机。
《柯林斯英汉双解大词典》
2
But to trigger the heart tripwires of a man, a movie has to focus on him staying true to his word, whether it's a promise made to a lover, a comrade-in-arms, or a sick grandson.
不过要想触动一个男人的心弦，电影的重点要在于信守诺言，不管这个承诺对象是恋人，战友还是生病的孙子。
3
In Sumatra in October, nature and man worked against the victims; most people didn't feel the earthquake strongly enough to trigger self-evacuation, and the tremor struck at night.