一.结构 : to do;(否定) not to do 二. 时态与语态 主动语态 被动语态 一般式 进 行式 完成式 完成进 行 式 不定式 to do to be done to be doing to have done to have been done to have been doing - -(1).不定式作主语时,往往放在谓语之后 ,用it作形式主语. To see is to believe. Its impossible for humans to fly like a bird now. My job to_. Your task to_ . is is (2).不定式作表语 protect the world. He likes to_. I find it still necessary (for him) to _ if he wants to win. (3) 不定式作宾语 play basketball 句型：think/ consider/ find it + adj.+ to do The teacher told me to_ I expect y
