n.惊恐;警报;闹铃;动员令;
vt.使惊恐;警告;给(门等)安装警报器;
例句:
The alarm spread rapidly.
警报迅速传开.
He was struck with alarm.
他饱受惊慌.
On hearing the alarm the fire brigade rushed to the scene.
消防队闻讯赶到.