people have heart trouble and other kinds of health problems ()this month

问题描述:

people have heart trouble and other kinds of health problems ()this month
填at among between during哪一个?为什么
答案是during

this month 是个持续的时间段,
at 用在某个时间点之前
among是三者或者三者以上之间
between是两者之间,
只有during是表示一段时间中发生什么事