抗议者威胁要放火烧政府大楼。

The protesters threatened to ___set ___fire ___to the government building.

盛怒之下，他烧掉了自己的旧信件。

In a fit of rage, he ___set his old letters ___on ___fire.

为了销毁他们存在的所有痕迹，间谍们放火烧了安全屋。

To destroy any trace of their presence, the spies ___set ___fire ___to the safe house.