21. The bottom mark on the board is red

3342. 按此顺序紧固螺栓是标准程序。

3341. Put on protective clothing when you use the solvent

3340. 在正常或异常的情况下,这些指令是必需的,例如从柔软的地面、湿滑的或结冰的表面上拖拽飞机并且在发动机被拆除或飞机损坏的状况下。

3339. This topic shall include general information, limits , and procedures In the maintenance manual this section shall cover subjects such as engine changes, run-up, externally-mounted spare power plants, etc

3338. This shows that you can install an alternative relay

3337. 布制品会勾在断了的导线上。

3336. This requires a breakdown of the job into logical steps or operations

3335. Unless the manufacturer＇s instructions tell you differently, do the procedure that fallows

3334. This is a recommended precaution to keep the center tank in good condition It is recommended that you do this procedure at intervals of 100 days

3333. Do not print on the back of the title page