9、Running helps to build up the muscles（肌肉）of my leg.
跑步可以增强我腿部肌肉.
1、—Could you please not follow me around?
请你不要跟着我好吗?
—Sorry,I won’t.
对不起,好的.
3、I’m sorry about that.I’ll play quietly.
不好意思.我会轻声玩的.
build up：树立,增进,增大
follow：跟随
around在...周围