动名词的否定形式与分词否定形式一样，由动名词前加not构成。
例句： She always has dozens of excellent excuses for not being able to help you.
分析： 该句是简单句。not being able to help you是动名词的否定形式。
译文： 对于未能帮助你，她总是有太多借口。
例句： She is considering not asking her mother to send her to the airport.
分析： 该句是简单句。not asking...作considering的宾语。
译文： 她正在考虑不让母亲送她去机场。
