如图所示单元体取自梁上哪一点?()
A.a
B.b
C.c
D.d
参考答案:C
解析:梁上a、b、c、d四点中只有c点横截面上的剪应力为负,同时正应力又为压应力。
(2011·江苏)The fact that so many people still smoke in public places ________ that we may need a nationwide campaign to raise awareness of the risks of smoking.
A.suggest
B.suggests
C.suggested
D.suggesting
尿液干化学分析仪通常由_______、_______、_______三部分组成。