关于骨巨细胞瘤,错误的是()
A.常侵犯骨端
B.内可有骨嵴形成的分房
C.骨破坏呈偏侧性
D.肿瘤内常有钙化,有骨膜增生
E.肿瘤一般不穿破软骨
参考答案:D
—Listen! Is Professor Johnson giving a report in the hall?
—No, it _____ be him. He has gone to Japan. [ ]
A. needn't
B. may not
C. mustn't
D. cannot