专家系统与传统的程序之间的最大区别是专家系统以______为处理对象，传统程序以数据为处理对象。
参考答案：知识
解析： 专家系统以知识为处理对象的。
The two pens are the same, but the red one cost _____________ that one.
A．as much twice as
B．twice as much as
C．much as twice as
D．as twice much as
油气最有利的生成地区是适于生物生活和大量繁殖，且水体宁静、（）含量低、具有还原环境，有利于有机物保存的环境。
A、空气
B、氧化
C、氢气
D、氮气
