They play the part that is expected from them,and with practice learn to.语法分析
问题描述：
They play the part that is expected from them,and with practice learn to.语法分析
They play the part that is expected from them,and with practice learn to play it very well.这句中的with practice 是介词with加practice作主语吗?好像不能这样做主语吗?
答
with practice 作的是状语they也是learn to play it very well的主语