园路的组成包括（）
A、路面、路基和道牙
B、基层和面层
C、面层、基层和结合层
D、主干道、次干道、支路
参考答案：A
When you are _______ about which button to press on the complicated machine, you can either read the user's guide for guidance or fax us for specific instruction. Don't ______ the trial-and-error method. [ ]
A. insure; do
B. ensure; make
C. uncertain; try
D. unsure; touch
新斯的明能对抗其肌肉松弛作用的是（）
A.琥珀胆碱
B.筒箭毒碱
C.毛果芸香碱
D.美加明
E.咪噻吩
