四、Windows的界面（三）
要求：打开“开始”菜单，删除快捷方式“记事本”
参考答案：开始→右击“记事本”→从列表中删除
—Why did you cancel your trip to the New York?
—We were just about to leave_______ it started to snow．
A．when
B．before
C．after
D．since
试述对厂用电源设计的要求？
