精馏要求塔顶产品和塔底产品(),不允许有()。
参考答案:同时合格;重叠
I have learned a lot about Asian customs, ______ in the small village for three years in the early 1990s.
A.lived
B.to live
C.having lived
D.to have lived
知识经济的发展要求建立()的公共决策体制。
A.多者博弈决策体制
B.民主参与决策体制
C.集权式决策体制
D.精英决策体制
E.网络化决策体制