男,34岁,体检摄片如图所示,最可能的诊断是()
A.氟骨症
B.转移性骨肿瘤
C.骨样骨瘤
D.骨岛
E.骨斑点症
参考答案:E
— Why is your bedroom so dirty?
— Sorry, Mum. It ___________. I felt very tired after playing soccer.
A.isn’t cleaned
B.didn’t clean
C.doesn’t clean
D.wasn’t cleaned
常规螺杆泵,用什么制造转子?用什么制造定子?