何谓油压?
参考答案:
油、气井油管内油气流在井口的剩余压力。
首次取得证书的人员实习操作不得少于一周,否则不得独立上岗。()
Practising Chinese kung fu can not only _____ one's strength, but also develop one's character. [ ]
A. bring up
B. take up
C. build up
D. pull up