拇指功能占手功能的比例约为()
A.20%
B.30%
C.40%
D.50%
E.60%
参考答案:C
—Where is Lu Wenjie?
—I have no idea.He__________ be in the library.
A.can
B.must
C.might
D.shall
简述推销人员的工作程序?