问题
选择题
“Shall Mary come and play computer games?” “No, _______ she has finished her homework.”
A．when
B．since
C．unless
D．as soon as
答案
C。
此句为省略句，答句句首的 No 表明其后省略的是一个否定句，全句补充完整为：She can’t play computer games unless she has finished her homework.
