简述维修方案的目的。
参考答案：（1）安全营运
（2）高的可靠性
（3）低的维修费用
（4）维修停场时间最短
（5）最好的客舱环境
用所给单词的适当形式填空
1. I can't understand you. Please explain it to me _______ (clear).
2. Haiku is _______ (simple) what is happening in this place, at this moment.
3. Do you know how to _______ (pronunciation) this word?
4. He felt very _______ (sleep) after the long walk.
5. To write poems needs _______ (imagine).
十字作业中紧固是指（）。
A.设备各润滑部位的油质满足要求
B.各连接部位紧固
C.有关间隙油压安全装置调整合理
D.各润滑部位连接紧固
