He looks young,为什么加S这里的LOOK为什么加了S?

He looks young,为什么加S这里的LOOK为什么加了S? 英语中的第三人称单数后加动词,为什么要加S?比如My father looks young. He looks very angry 为什么look后面要加s he looks young,right?yes ,l think s[ ]. The sky looks blue.为什么looks要加s? your friend looks very young 请问为什么这里的look要加s如果分别是your friends 与 your friend 该怎么加. Tony's grandfather is a___ He looks like a young man. the photo looks beautiful这里的look为什么加s 还有He has a great sports collection的sport为什么加s He did not look like a evil person . He looks lHe did not look like a evil person . He looks like a southerner 这2个什么区别为什么一个加s一个不加? .My grandfather looks very young because he exercises every day.为什么用exercises She looks worried.look为什么要加s It looks nice.为什么look要加s. Althouth he is old ,but he looks young.改错 he looks young a____ he is 60 years old He 's good at doing sports,so he looks very h后面应该加什么单词, -The man in his__is my father.-Wow,he looks really young.A.fortyB.fortiethC.fortiesD.forty's并说明理由 look后面什么时候要加s啊比如He looks like his father 后面为什么要加s而He look and his facher look the same 后面为什么不要加s而He and his father have the same look后面为什么也不要加s他们的主语不都是三单吗 my grandpa is old ,--he looks young .怎么写?