Unit 6 Unit 6 Ford's Assembly Line icomsohho hs made differene in all that Henry For orian a century from now migh who most d all facturin ng a new way to make cars e if it v ould sr nroduction of a nart of an a ine calla ach worker comnktely assemble a magneto.one of its cloments was nlaced on a convever,and each worker,as it passed,added another component to it.the same one cach time.Professor David Hounshell of the University of Delaware. an expert on industrial development.tells what happened: "The previous day,workers carrying out the entire process had averaged one assembly every 20 minutes.But on that day.on the line,the assembly team averaged one every 13 minutes and 10 seconds per persons.' Within a year.the time had been reduccd to five minutcs.In 1913,Ford went all the way.Hooked together by ropes.parially aembled vehicles wer turning out several hundred th cars a yearaem And so em affor ge of the automo hasarrived.Today,aided by robots and other forms of automation verything
from toasters to perfumes is made on assembly lines. Words and Expressions ,装配：会 烤面包机：面 mble [kem ,聚集 ughterhou司n,居率场 automation[o:/mifn】.白动化 overlook [ouvo'lul 。忽视：宽彩 均数 日
0ni证7 Unit 7 Tire mpct with bump and chuckholes tire. Tires not only support the full weight of the vehicle but also provide a cushion of air betwoen the vehicl and ground.The tire envelopes the small road discontinuitics.smoothing out the vibrations and jarring that would otherwise be felt in the vehicle. One of the most important features of a tire is traction.Tires come in a wide variety of read pattemns to provide varying degres ofction A uir for high traction on slippery surfaces may have an undesirable ois witching tires or y irferet tmllrd all weather tread tire incorporates sperial crisscross grooves along with circumferential grooves to channel water from under the tread more efficiently for improved wet traction.Italso has wedge shaped tread lugs to provide snow traction andit is relatively quiet on dry roads
Words and Expressions ,轮的面 。不合需的。不 chckhoe['xkhaul]n.马路上的航或H处 受建的，令人 et] 不快的 子， incorporate [in'] .合并 jar [dge] .《轮或车对站 circumferential Notes wide varicty of tread pattems to provide varying 轮的冠花纹不，对地面的抓着力不同 ombines the characteristics of ns into all weather tread 轮胎制造商综合各种轮胎花纹的特点，开发适用于所有天气的胎面花纹
Unit 8 Unit 8 Fahrenheit and Celsius Daniel Gabriel Fahrenhcit and Andkers Celsius both began workon their 18th century. a r.Fahrenheit siderab experin 10m and n kd the 12. uld of a water.ice.and salt solution m the temm of the human body Eabrenbcit belicved that the thermometer he invented in 1714 had eight times the accuracy of Newton's thermometer,and therefore 96 degrees should scparate thesc benchmarks (eight times Newton's range).Using this new scale.a combination of water.ice and salt solution stayed at o'.and body temperature registered as 96.With these marks intact,a combination of water and ice (the freezing point)equated 32'.Scientists later found that water boiled at 212according to the Fahrenheit scale.After more accurate testing 95.6 the body temperatur today bit ater in 72.point and to the boiling point appeared in den an France but with the nun The Celsi work in 194 of this parts of the world while the offers this the of the is that