问题
选择题
A stubborn boy like him dosen’t learn from his mistakes______ he was punished badly.
A.if
B.when
C.since
D.unless
答案
答案:D
考查连词,if 如果, when 当什么时候,since 自从,unless 除非,句意:像他这么笨的男孩根本不会从错误中学习除非除非他受过严重的惩罚。所以选D。