分层开采就是根据生产井的开采油层情况,通过井下工艺管柱把各个目的层分开,进而实现() 发布时间:2017-06-21 21:13 │ 来源:www.tikuol.com 题型:单项选择题 问题: 分层开采就是根据生产井的开采油层情况,通过井下工艺管柱把各个目的层分开,进而实现()的目的。A、分层注水B、多注水、多采油C、分层采油D、分层注水、分层采油
题型:单项选择题 Two-thirds of the land ________ covered with green grass and the rest _______ covered with pine trees.A.is; isB.is; are C.are; isD.are; are 查看答案