问题
Jane will have to________her piano practice a longtimeif she wants to be a professional concert performer. [ ]
A: set up
B: add up IMG style="WIDTH: 1px; HEIGHT: 1px; VERTI
C: keep up
D: hold up
B: add up IMG style="WIDTH: 1px; HEIGHT: 1px; VERTI
C: keep up
D: hold up
正确答案是：
