用药前须做皮试的药物是
A.普鲁卡因
B.青霉素
C.链霉素
D.红霉素
E.环丙沙星
参考答案:A,B
解析:普鲁卡因、青霉素主要不良反应为变态反应,使用前必须做皮试。
—Sally failed in this math test. She is very sad now.
—Let’s go and_______.
A.laugh at her
B.cheer her up
C.let her down
D.learn from her
客专线维修工作分为周期修、状态修和()。