—The government plans to build a big power station along the river bank.

— Good news! So we and the neighboring areas will get great      from it.  

A．value

B．benefit

C．cost

D．profit

网络全文搜索引擎—般包括搜索器、检索器、用户接口和______。

A．索引器

B．机器人

C．爬虫

D．蜘蛛