毛细管力在采油中的影响都是不利的。
A. 对
B. 错
油井完井和井下作业中,由于贾敏效应,常会使井的产量降低。
A. 对
B. 错
Elizabeth decided to make her ____ plan because she will graduate next term.
A. profession
B. career
C. vocation
D. occupation
The price ____ is still upwards, and many housewives find it hard to afford daily items.
A. trend
B. drift
C. tide
D. float