SAT语法句子改错题是Writing Skills中的一个小题型，语法一直都是中国学生的一个弱点，所以要加强练习。本题提供了答案和解析，请大家参看。
The following sentence contains either a single error or no error at all. If the sentence contains an error, select the one underlined part that must be changed to make the sentence correct. If the sentence contains no error, select choice E.