电弧焊接时,不小心看到的刺眼光线是()。
A、紫外线
B、红外线
C、可见光线
D、放射线
参考答案:C
According to the newsman, as a result of_____ heavy fog, _____ expressway has been closed up until further notice.
A.a; the
B.the; 不填
C.不填;an
D.the; the
正畸的最终目标是将牙列矫正为()
A.错
B.早接触
C.干扰
D.平衡
E.个体正常