重点句型
1. Their use was limited by laws, the first of which dates back to the fourteenth century.
面具的使用受到法律的限制，最早可追溯到14世纪。
2. If they broke the laws, they were put into prison for up to two years.
如果他们违犯法律，就要被判处长达两年的监禁。
3. If the masks come off, the magic is lost.
如果面具摘掉了，魔力也就消失了。

句型探究
1. Their use was limited by laws, the first of which dates back to the fourteenth century.
面具的使用受到法律的限制，这最早可追溯到14世纪。
(1)该句中the first of which...是一个非限制性定语从句，修饰先行词laws。
(2)date back to 相当于date from,意为“追溯到,始于”;常用于一般现在时,无被动语态。
Their friendship dates back to their childhood.
他们的友谊始于儿童时代。
2. If they broke the laws, they were put into prison for up to two years.
如果他们违犯法律，就要被判处长达两年的监禁。
(1) put sb. into prison (prison前无冠词)
=send sb. to prison 把某人送进监狱
be in prison 坐牢
(2) up to
①达到(数量,程度);至多有
I can take up to four people in my car.
我的汽车最多能坐4个人。
②直到
Up to now, he has been very quiet.
直到目前，他一直很安静。