要提高岩心收获率,必须对取心的技术措施、操作技能、取心工具等方面进行深入的分析研究,逐步提高取心钻井的工艺技术水平。
参考答案:对
With his blows knitted, the doctor contemplated the difficult operation he had to perform.
A.succeeded in
B.decided against
C.went on with
D.thought deeply about
开清棉机械联动的控制方法有()、()和()。