Swimming is very interesting.为什么不能说swimswim也是名词啊,为什么用动名词（详细解释下）动名词和名词的用法上有哪些区别?

swimming is very Swimming is very popur in summer.(翻译) Swimming is very popular in summer. john likes swimming very much.and he is a good( ). Swimming is very popular in summer 整篇文翻译 Swimming is very popuar in the world .翻译 swimming is very popular in summer同义句 Swimming is an a_____;I enjoy it very much He studies English very well and 后面跟good at swimming还是is good at swimming Tom loves swimming because it is very interesting 对because it is very inter he likes swimming very much .同义句是什么?he is （ ） （　　）（　　）swimming.多了一个空。 It's very hot.( )is nice to go( )in the sea.A/That;swimming B,It;swimming,求详解 Luo Xuejuan is a very good s______and she is good at swimming. Mr.Zhou is the___(领导)of the school swimming team,he is very strict with us. 同义句转换swimming in the sea is very dangerous= （） is very dangerous （）（）in the sea This is Amy .She is not very tall .She has short hair .She is good at swimming .She is funny . ()being fun and good exercise,swimming is a very useful skill _________being fun and good exercise,swimming is a very useful skill.填空