阿兰•图灵（AlanTuring）是（）数学家、密码学家、计算机科学之父。
A.美国
B.英国
C.德国
D.意大利
参考答案：B
—Would you mind answering some questions on shopping habits?
— ________.
A．Yes, with great pleasure
B．No, I am afraid I can't make it
C．Yes, it is worth the time
D．No, as long as it doesn't take long
可作渗碳零件的钢材是（）和（）.
A.08
B.20
C.40Cr
D.55
