英语语法分析

He just looks grumpy because of his underbite, wrinkles, and dark complexion.

它之所以看起来不爽是因为它反颌，皱纹和深色的肤色。

The vet said he's as healthy as any other puppy. He just looks grumpy because of his underbite, wrinkles, and dark complexion.

兽医说他和其他小狗一样健康，之所以看起来阴郁是因为他‘地包天’的上下颌，皱纹，以及深色的皮肤。