they looked happy和they looked happyily那个是对的?为什么?

题目

they looked happy和they looked happyily那个是对的?为什么?
His dog always looks happily at him when he gets hone from school every day.这句肯定是对的,但我看别人不是这么说的,我搞不清

答案

They looked happy.是说他们看起来很高兴.happy 是形容词.
His dog always looks （happily） at him when he gets home from school every day.
也是对的.因为这里 这里 happily 是副词修饰 looks at ..看着.
他每天一回到家他的狗就很开心的看着他.
这里happily 也可以换些位置,比如.
His dog always looks at him happily when he gets home from school every day.