extensions 的意思是

263 As only approved limitationsmay beincluded in thisSection,an introductory statement to this effect shall be contained in aprefatory note or the opening paragraph.

262 BAPPROXIMATE

261 An important occurrence thatcan cause damage or have dangerous results.

260 Always obey the precautions that follow tokeep electrical wiring ina satisfactory conditions.

259 All range distances shall be expressed in nautical miles

258 After the ailerons go back toneutral make sure they are flush with the flmps.

257 Add a washer if necessary.

256 ABSORB

255 这种材料接触热表面时会释放出危险的气体

254 系统内的所有流里控制装置,如单向活门、燃油泵、储压器和继电器均应包括在内。