1、肯定形式：主语+动词过去式+其他。 例句：She often came to help us in those days. 2、否定形式： （1）was/were+not； （2）在行为动词前加didn't，同时还原行为动词。例句：I didn't know you like coffee. 3、一般疑问句： （1）Did+主语+谓语动词原型+其他；例句：Did I do homework?...