1．I was_about_to_go back to sleep when suddenly my bedroom became as bright as day.
我刚要睡，突然我的卧室亮如白昼。
be about to do sth. when... 正要干……这时……
①I was about to go out when the telephone rang.
我正要出门，这时电话铃响了。
②The meeting was about to be held when it began to rain.
会议正要开始，这时开始下雨了。
