My favorite sport is playing table tennis .请问；为什么要用playing?

(skate)is my favorite sport . football is my favorite sport. My favorite sport is 什么什么 My favorite sport is play tennis改错 my favorite sport is soccer正确吗? I LIKE. BUT MY FAVORITE SPORT IS . 选择填空 Hi,Tom!What is your favorite sport My favorite sport is My Favorite Sport 作文 My favorite sport My favorite sport is skating.skate为什么要加ing? My favorite sport is skating .I skate __ My favorite sport is skating.(同意句转换） My favorite sport is swimming.可以用于写作文吗? MY favorite sport is tennis 用tennis提问 Playing basketball is my most favorite sport.改错 My favorite sport is soccer and running.正确吗 "my+favorite+sport+is+swimming"怎么改错 Football is my favorite sport.的同义句