颈动脉海绵窦瘘最常见的病因是
A．颅内感染
B．硬脑膜动静脉瘘
C．颅内动脉瘤
D．头部外伤
E．颈内动脉发育异常
参考答案：D
Not only Tom but also Jack ______ to that city several times.[ ]
A. have been
B. has been
C. have gone
D. has gone
The money was soon spent , so he ____ go hungry .
A．must
B．had to
C．might
D．should
