be 动词是时态是过去时,was ,后接动词如果是被动语态的话,后接动词加ed 如,This book was written by me. 此句中be动词由于时态是过去时,为was,而书是被写的,被动语态,则 written
谓语动词有行为动词,系动词,情态动词和助动词,行为动词包括及物动词和不及物动词。
be谓语动词中的系动词
do是其中的助动词 后面接动词原形,Did you go swim yesterday?
can 等等是 情态动词 后接原形 Can you swim?
行为动词 有被动与主动之分 I went for a walk this morning.
至于你的第三个问题,我没有看明白。能否举例具体说明下?
贴下此贴,
http://baike.baidu.com/view/330413.htm?fr=ala0_1