action
n.行动;行为;作用;情节
The government must take action now to stop the rise in violent crime.
政府现在必须采取行动阻止暴力犯罪的上升。
activate
vt.使活动起来，使开始起作用
Cooking fumes may activate the alarm.烹调时的油烟可能会触发警报器。
activity
n.活动，行动;活跃，活力
outdoor activities such as hiking or climbing
远足或爬山等户外活动
acute
a.严重的,激烈的;敏锐的;急性的;尖的
The housing shortage is more acute than first thought.
住房短缺情况比一开始想的要严重。
