问题描述：
I felt somewhat disappointed and was about to leave,___ something occurred attracted my attention.
[A] unless [B] until [C] when [D] while
为什么选C?请翻译句子
[A] unless [B] until [C] when [D] while
为什么选C?请翻译句子
问题解答：
我来补答展开全文阅读