什么是限定动词和非限定动词?

英语上根据动词在句法上是否受到主语的限定,英语动词有可以分为限定动词(Finite Forms of Verbs)和非限定动词(Non-Finite Forms of Verbs).
限定动词又叫谓语动词,在句中充当谓语,在人称和数上必须和主语保持一致,同时还表现出时态、语态和语气的变化.如：
I play basketball.
He plays basketball.
They played basketball yesterday.
The cars are made in China.
非限定动词,又叫非谓语动词,在句中不能单独充当谓语（但可以和情态动词或助动词一起充当谓语）,它们不受主语的限定,没有人称和数的变化,具有名词、形容词和副词的特征,在句中可以充当主语、宾语、表语、定语、状语、补足语等.同时非限定动词也保留了动词的部分特征,有时态和语态的变化,也可以有自己的宾语、表语、状语等,构成非限定动词短语,在逻辑意义上也有其动作的执行者或承受者,叫非限定动词的逻辑主语(Logical Subjects).
英语非限定动词有三种基本形式：不定式(Infinitives)、动名词（gerund）、分词（现在分词ing Participles和过去分词ed Participles).
1.不定式
(1) Jean aims to go tomorrow.
(2) I was delighted to meet him.
(3) The clothes are easy to wash
2.动名词
（1）Reading is an art.
（2）Swimming is a good sport in summer.
3.现在分词
（1）I saw the dog digging holes in the yard.
（2）Hearing the news,they immediately set off for Shanghai.
（3）He walked down the hill,singing softly to himself.
（4）If traveling north,you must change at Leeds.
4.过去分词
（1）developed country; fallen leaves; lost child
（2） Half of the guests invited to the party were foreigners.
（3）She can’t make herself understood in English