● 动名词由动词原形加词尾-ing构成。动名词是名词性的，具有动词特征和名词特征，在逻辑上表达的是一个动作（或状态），在语法上体现的是名词特征。

● 动名词的名词特征体现在可以用作主语、宾语等。如：

Preparing for the Olympic Games is a huge undertaking. (preparing作句子的主语)

Without preparing a strong bid, …(preparing作介词without的宾语)

Do you like watching football games?(watching作动词like的宾语)

● 动名词的动词特征体现在可以有宾语和状语。如：

Hosting the games has a major effect on the economy.(hosting作句子的主语, 同时带有宾语the games)

After winning the bid, Beijing began major construction projects.（winning作介词after的宾语, 同时带有宾语the bid）