如果您是想理解为什么有时会在 every 后面加上 single 的话.
没有区别,只为强化语气罢了.
比如：
I know every one of them.
I know every single one of them.
或
I've been doing exercise every day for the past 3 weeks.
I've been doing exercise every single day for the past 3 weeks.
意思完全一样,只不过有时说话的人想要强调一下而已.