用户中心
学员疑问：老师，下面这个句子中两个that的用法一样吗，都是引导定语从句？
The same dramatic technological changes that have provided marketers with more (and more diverse) communications choices have also increased the risk that passionate consumers will voice their opinions in quicker, more visible, and much more damaging ways.
老师解答：第一个that引导定语从句，修饰先行词（dramatic technological）changes，that代替先行词在从句中充当主语；第二个that引导同位语从句，that在从句不充当成分。
点评分析：that引导同位语从句和定语从句时容易混淆，因为前面都有名词，区分的依据是看that是否在在从句中充当成分。这里，补充一下，其实that可以引导各类从句，包含名词性从句（=主语从句、表语从句、宾语从句、同位语从句）且在从句中不充当成分，形容词性从句（=定语从句）且替代先行词在从句中充当成分，副词性从句（=状语从句）如结果状语从句（so that…）。到底怎么用，还得根据句子结构和逻辑意思综合来判断。
