下贝氏体在显微镜下所呈现出的形态是（）
A.针状
B.球状
C.羽毛状
D.片状
参考答案：A
______ your teacher the problem with learning, theoretically, and they will help you.
A．Telling
B．To tell
C．Tell
D．Having told
3PE防腐钢管露天放置超过6个月，为防止翘边的发生，采取的最佳办法是（）.
