was(或者were) used to + 名词或者动名词,就是过去习惯于某事.例如：I was used to the hot weather in southern China.我以前很习惯中国南方的热天气.
used to +原型动词,有两个意思,一个就是过去常常,另外一个是曾经.例如：
He used to play computer games,but now he doesn't.他以前常常打电脑游戏,现在不打了.
I used to be in the school basketball team.我以前曾经隶属学校篮球校队.