句子:Dudley had spent most of the summer in the kitchen, his piggy little eyes fixed on the screen and his five chins wobbling as he ate continually.
问题:his piggy little eyes fixed on the screen and his five chins wobbling 这个句子是独立主格吗?主要修饰前面的主句“Dudley had spent most of the summer in the kitchen”吗?
谢谢!!