由于大型铸件常常有枝晶偏析出现,所以其预先热处理需采用()。
A、正火
B、完全退火或球化退火
C、高温回火
参考答案:B
By hiking, people can ______ nature and experience a kind of life.
A.close to
B.close the
C.get close to
D.get close to the
仅在膀胱充盈时才漏尿为()
A.膀胱 * * 瘘
B. * * * * 瘘
C.输尿管 * * 瘘
D.直肠 * * 瘘
E.膀胱宫颈瘘