She read the letter loudly ________ all the families could hear.(单选题)

问题描述:

She read the letter loudly ________ all the families could hear.(单选题)
because
since
when
so that

答案:so that(以致于)解释。。这是根据整个句子的意思来判断的,因为句子的意思为:她大声地念出这封信,以致于全家人都能听得见。这里用so that主要表示目的,就是想达到某种结果的意思。而其他的几个选项都不符合这里的语言环境。明白了吗?