be done属于被动式的原型。它有is done, are done的单数和复数形式。要做谓语的。如
The work can be done this week.
而done是过去分词。它不能做谓语，但可做补语，表语。 定语和状语，表示和所修饰词之间的被动关系，如
The meeting held yesterday is very important .句中的held 是定语
I had my hair cut 。句中的cut是补语。
Compared with others , you are lucky. compared是状语。
We were excited when we heard the news. excited是表语。
