问题补充:
The weather that day may not be as good as expected, in case we will have to put off the event.
A. what
B. that
C. this
D. which
答案:
A. what
B. that
C. this
(答案→)D. which
解析:考察定语从句关系代词的用法。Which在本句中作定语修饰case,in which case指在那种情况下。句意:那一天的天气也许不像预料的那么好,在这种情况下,我们将推迟这项活动。