1.肯定式
2.否定式
（1）not doing
Not being punctual makes him unreliable.不准时使人觉得他不可靠。
（2）not having done
I’m surprised at your not having noticed.你竟未注意到我感到吃惊。
（3）one’s not doing
Jenny’s not having been trained as a dancer is her one regret.
杰妮没受过舞蹈的专业训练是她感到遗憾的事。