B． with
C． without
D． in
[试题]Part A51. Directions：Write a letter to your university library, making suggestions for improving its service.You should write about 100 words on ANSWER SHEET 2.D．o not sign your own name at the end of the letter. Use “Li Ming” instead.D．o not write th
[试题]Part A51. Directions:Restrictions on the use of plastic bags have not been so successful in some regions. “White pollution ”is still going on. Write a letter to the editor(s) of your local newspaper to1) give your opinions briefly and2) make two or th
51.什么叫准静态过程51.(简答题，10.0分)什么叫准静态过程
51．木工作业不包括()。A. 砂磨B. 调和黏土C. 刨木D. 锤钉E. 旋拧螺钉
51.β-衰变产生的射线是 ( )A. 是氦的原子核B. 是光子C. 是不稳定原子核发射的电子D. 是核外电子E. 正电子也可能是负电子
51.个人移动辅助器具不包含( )。A. 脚踏三轮车B. 护腰带C. 老年代步车D. 可调台式助行器
[多选题]51.标准化工作的任务是（）A.）制定标准B.）组织实施标准C.）标准的实施进行监督D.）认证认可
51.诊断肾癌最有价值的检查是（）A. 肾动脉造影B. 静脉尿路造影C. 磁共振D. B 超E. 增强 CT
51.世界电影诞生于1895年的法国。()A. 对B. 错
51.测量产状可以用指南针A. 对B. 错