痈的致病菌是
A．溶血性链球菌B．绿脓杆菌C．大肠杆菌D．梭状芽孢杆菌E．金黄色葡萄球菌
参考答案：E
—When is your birthday?
—It's ______. [ ]
A. January
B. second
C. January second
D. 1990
简述圆筒的纵缝装配。
