737-300與 737-200具有相同的基本設計，機體伸長了 104英寸，翼尖延伸了 14英寸，水平尾翼延伸了 36英寸，還多了個大的脊鰭和增強的水平尾翼。

(8) The 737-400, relative to the 737-300, has body stretch of 120 inches, tow

additional overwing exit, tail skid, and strengthened landing gear.
737-400與 737-300相比較，機身伸長了 120英寸，多了兩個逃生出口，尾部滑軌及加強了起落架。
(9) The 737-500 uses the 737-300 basic structure with a 94 inches shorter body and a revised forward and aft fairing (wing to body).
737-500使用了 737-300的基本結(jié)構(gòu)，機身短了 94英寸，并且修改了前后整流罩（機翼到機體）。
LESSON 2 THE PNEUMATICS SYSYTEM增壓系統(tǒng)
一、生詞
目的  Purpose 壓縮空氣  compressure Air 壓縮空氣  pneumatic
環(huán)境  Environment 階段，相位  Phase 得到  Obtain
發(fā)動機引氣  Engine bleed 外部的  External 車  Cart
接頭  Connector 整流罩  Cowl 熱的  Thermal
防冰  Anti-icing 也，此外  Also 提供  provide
飲用水  Potable water 液壓的  Hydraulic 啟動器  Starter
在 …之內(nèi)  Within 正常的  Normal 取代  Substitute
滿足  Meet 需要，要求  Need 上部、頂部  Top
圖形  Figure 絕緣  Isolation 活門  Valve
管道  Duct 結(jié)合、連接  Join 交叉、跨接  crossover
管理、調(diào)整  govern 適當?shù)?nbsp; appropriate

二、TEXT
(1) the purpose of the pneumatic sysytem is to supply compressed air for a controlled temperature and pressure environment during all phases of flight and ground operation .air is obtained from engine bleeds. APU、or from an extermal ground cart through a connector located on the fuselage.

增壓系統(tǒng)的作用是為飛行及地面所有階段的溫度和壓力控制提供壓縮空氣。壓縮空氣的來源可以是發(fā)動機引氣、 APU、或通過機身上的連接頭與地面氣源車相連供氣。

(2) The pneumatic system controls the temperature and the pressure of engine bleed air source. The pneumatic system provides high temperature, high

pressure air for the air conditioning .pressurization, wing and cowl thermal anti-icing .also, the pneumatic system provides pressure for the potable water system, hydraulic system and engine starters. The engine bleed air systems are located on the engine and within the support strut.
增壓引氣控制發(fā)動機引氣的溫度和壓力。增壓系統(tǒng)為空調(diào)、增壓系統(tǒng)、機翼及整流罩熱防冰系統(tǒng)提供高溫、高壓引氣。同時，增壓系統(tǒng)還給飲用水系統(tǒng)、液壓系統(tǒng)和發(fā)動機起動系統(tǒng)提供壓力。發(fā)動機引氣系統(tǒng)位于支架內(nèi)部發(fā)動機上。
(3) The normal cabin air source is obtained from the 5th-stage of the engines at low –engine power, 9th-stage air automatically substitutes to meet user system needs.

正常情況下，客艙空氣來自于發(fā)動機低能量的第 5級， 9級空氣自動分配以滿足用戶系統(tǒng)的需要。

(4) On the top of figure 2-1, the isolation valve separates the left and right halves of the system. On the left side of the isolation valve, the APU bleed air duct joins the left side crossover duct; on the right side ,the pneumatic ground service connector joins the right side crossover duct. From these ducts the user system are supplied with pressurized air ,governed by the appropriate control valves.