问题补充：
非谓语动词有哪些,请列举并说明
答案：
非谓语动词包括动词不定式、动名词和分词.动词不定式可在句中作主语、表语、宾语、宾语补足语、定语和状语；动名词可在句中作主语、表语、宾语和定语；分词可在句中作表语、宾语补足语、定语和状语,现将它们在用法上的区别总结如下：
1动词不定式和动名词作主语比较
动名词作主语表示一般或抽象的多次性动作,不定式作主语表示具体的或一次性的动作,特别是将来的动作.例如：
_______ is a good form of exercise for both young and old．（MET 1992）
A．The walk B．Walking C．To walk D．Walk（Key：B）
2动词不定式、动名词、分词作表语比较
（1）不定式和动名词作表语的区别同作主语一样.
His job is building houses．
Our task now is to increase food production．
（2）动词不定式和动名词作表语说明主语的内容,现在分词作表语表示主语所具有的特征,过去分词作表语表示主语所处的状态.
The real problem is getting to know the needs of the customers．
The most important thing is to put theory into practice．
The purpose of new technologies is to make life easier,_______ it more difficult．（NMET 1999）
A．not make B．not to make C．not making D．do not make （Key：B）
3动词不定式和动名词作宾语比较
（1）有些动词后只跟不定式作宾语,如：want,wish,hope,manage,de- mand,promise,refuse,pretend,plan, offer,decide,agree,expect等.
We agreed _______ here,but so far she hasn turned up yet．（NMET 1995）
A．having met B．meeting C．to meet D．to have met （Key：C）
（2）有些动词后只跟动名词作宾语,如：admit,appreciate,avoid,con- sider,delay,dislike,enjoy,escape, excuse,finish,forgive,imagine, keep,mind,miss,practise,resist, risk,suggest,deny等.
The squirrel was so lucky that it just missed_______ ．（MET 1987）
A．catching B．to be caught C．being caught D．to catch （Key：C）
I would appreciate_______ back this afternoon．（MET 1992）
A．you to call B．you call C．you calling D．you e calling（Key：C）
（3）有些动词后既可以跟不定式又可以跟动名词,意义上无多大区别,如：love, like,hate,prefer,intend,start, continue等.
I intend to finish/finish- ing the task this morning．
（4）有些动词后既可以跟不定式,又可以跟动名词,但意义上有区别,如：forget,remember, mean,regret,stop,try等.
—The light in the office is still on．
—Oh,I forgot _______ ．（MET 1991）
A．turning it off B．turn it off C．to turn it off D．having turned it off（Key：C）
—You were brave enough to raise objections at the meeting．
—Well,now I regret _______ that．（NMET 1995）
A．to do B．to be doin
