紫外光可以诱杀害虫、消毒灭菌，大剂量紫外光会使生物发生病变甚至致死。( )
参考答案：对
The driver turned his car sharply to the left to give the way to the running bull only _________ a tree by the road.
A．to knock into
B．knocking down
C．to knock at
D．knocked over
进口押汇期限按实际天数计，但最长不得超过（）天。
A.30
B.60
C.90
D.180
