Everyone should learn something about first aid.for every second will in an emer

Everyone should learn something about first aid，for every second will ________ in an emergency.

试题答案

B

解析句意为：每个人都应该学点急救知识，因为在紧急情况下每一秒都很重要。play玩； count起关键作用；happen发生； show展示。