火灾警报用英语可以表示为 "fire alarm" 或者 "fire warning."

"Fire alarm" 来源于中世纪拉丁语 "alarma"，意思是"警报"或者"惊恐." 在英语中，"alarm" 一词有时也用来形容其他类型的紧急情况，比如"burglar alarm" (防盗报警器) 或者 "smoke alarm" (烟雾报警器).

"Fire warning" 则来源于英语动词 "warn," 意思是"警告"或者"预先告诉."

下面是一些使用 "fire alarm" 和 "fire warning" 的英文例句及其中文翻译:

The fire alarm went off, so we all had to evacuate the building. (火灾警报响起，所以我们都必须撤离建筑物.)
The fire department was alerted by the automatic fire alarm. (消防部门被自动火灾警报器报警.)
We received a fire warning on our phones, telpng us to evacuate immediately. (我们在手机上收到了火灾警报，告诉我们立刻撤离.)
The fire warning system alerted us to the presence of smoke in the building. (火灾警报系统提醒我们建筑物内有烟雾.)