问题
选择题
That day, we______ for the train station when Tom fell and hurt his legs badly.
A．have been leaving
B．were just about to leave
C．have left
D．are just going to leave
答案
答案：B
题目分析：考查固定句式。固定句式be doing sth/be about to do sth when…正在做某事在这时发生了意料之外的事情。When是一个并列连词，意思为“在那时”句意：那一天，我们正要出发去车站，在这时Tom摔倒了伤到了他的腿。故B正确。
点评：本句式中的when是一个并列连词“在那时”；后面引导的是一个并列句。要特别注意be doing sth/be about to do sth when…正在做某事在这时发生了意料之外的事情。
