动词-ing 形式作主语和宾语1. 动词-ing 形式是在动词末尾加 -ing ， 属于非谓语动词。如：do-doing, write-writing, sit-sitting, etc. 否定形式：not + v-ing 2. 动词-ing 形式作主语或宾语时，也 可称为动名词。动词-ing 形式作主语 1. 动词-ing 形式作主语表示抽象的或泛 指的动作, 谓语动词用单数。如： Reading aloud is very important for us to learn a foreign language. Going to bed early and getting up early is considered to be a good habit.2. 动词-ing 形式作主语时常后置, 用it 作形式 主语，用形容词或名词作表语。常见的作 表语的名词或短语有：no use, no good, fun, hard work, a hard / difficult job, a wonder, a waste of time 等。如： Is it worthwhile qu
