缺陷的检测方法中,说法正确的是()。
A、渗透探伤可以检查容器内部缺陷
B、超声波测厚仪可作非破坏检查
C、无损探伤会对容器造成破坏
D、射线探伤主要用于检查容器外部缺陷
参考答案:A
结构化程序设计的3种基本结构是______。
A.过程、子程序和分程序B.顺序、选择和循环C.递归、堆栈和队列D.调用、返回和转移
His parents wouldn't let him marry anyone _____ family was poor. [ ]
A. of whom
B. whom
C. of whose
D. whose