The British government often says that providing children with ________ to the information superhighway

is of great importance.[ ]

A．prevention  

B．protection

C．allowance  

D．access

船上吊缸检修一般不必（）。

A.用通针疏通针阀体和喷孔

B.清除燃烧室零件表面积炭

C.拉出气缸套进行磁粉探伤

D.清除气口堆积物