钻石的亭深比可以用（）检验。
A.游标卡尺
B.钻石卡尺
C.10倍放大镜
D.量规
参考答案：C
Where have you been all these days? We are very _____ about your safety. [ ]
A. interested
B. frightened
C. surprised
D. concerned
下列征象中，对周围型肺癌诊断价值最大的是（）
A.斑点状钙化
B.分叶及毛刺
C.空洞
D.周围无卫星灶
E.支气管气相
