105. This has also resulted in an increase in the sheer number of advertisements to which audiences are exposed.
译文
这也使得观众能看到的（电视）广告的数量大量增加。
点睛
本句的主干是this has also resulted in an increase。to which audiences are exposed是由“介词＋关系代词”引导的定语从句，修饰先行词advertisements。
sheer的意思是“完全的，十足的”，表示幅度大；sheer number指“巨大的数量”。be exposed to的意思是“接触；面临”。
考点归纳
由“介词＋关系代词”引导的定语从句须注意的几个问题。
关系代词which和whom在定语从句中作介词的宾语时，介词可放在关系代词之前，也可放在该定语从句中的动词之后（此时，which可用that代替，whom可用who或that代替。在口语和非正式文体中，关系代词可以省略）。如：
On the isolated island, there wasn't a single person to whom she could turn for help. 在这座孤岛上，没有一个她可以寻求帮助的人。
此句可以改为：
On the isolated island, there wasn't a single person (who/whom/that) she could turn to for help.
关系代词that在定语从句中作介词的宾语时，介词只能放在从句中相关动词之后，不可放在that前面，但that可省略。如：
1) The house (that) we live in is not large. 我们住的房子不大。（√）
2) The house in that we live is not large.（×）
在由“代词＋of＋关系代词”结构引导的定语从句中，先行词指“人”时用whom，指“物”时用which。如：
1) There are 50 students in my class, most of whom are girls. 我们班上有50个学生，其中大多数是女孩。
2) Finally he finished the paper, most of which was downloaded from the Internet. 最后他终于完成了论文，但大部分是从网上下载的。
