噪声能影响人体的神经系统,使人易怒和急躁。
参考答案:对
In fact, smokers know that smoking has a bad ________on their health, but they just can’t stop it.
A.result
B.effect
C.aspect
D.impress
在确定数控车床坐标系中,X、Y、Z中者的关系及正方向时,用()
A.右手定测
B.右手螺旋法则