I love playing the piano 我喜欢弹钢琴. play后为什么要加ing? 希望能解释的详细一点.谢

I love playing the piano 我喜欢弹钢琴. play后为什么要加ing? 希望能解释的详细一点.谢 he practices playing the piano every daay为什么play要加ing而 I see he practices playing the piano every daay为什么play要加ing I practise playing the piano中“playing”为什么要加ing? I like playing volleyball为什么play要加ing? i like playing basketball为什么要在play后加ing 为什么Playing football.Play要加ing he likes playing basketball.他喜欢打篮球 .为什么play要加ing Lucy like playing sports 为什么play后加ing i like playing basketball 为什么play加ing 弹钢琴是我的爱好Playing the piano is my hobby还是playing piano is my h I think playing basketball is interesting里为什么play要加ing