首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Plastics are materials which are softened by heat and set into last form 1.______ when are shaped in a mold. Some are natural; s
Plastics are materials which are softened by heat and set into last form 1.______ when are shaped in a mold. Some are natural; s
admin
2011-07-28
47
问题
Plastics are materials which are softened by heat and set into last form 1.______
when are shaped in a mold. Some are natural; some are semi-synthetic, the 2.______
result of chemical action on natural substance; some are synthetic, built up
from the constituents of oil or coal. All is based on the chemistry of carbon, 3.______
with its capacity of forming chains. The molecules that compose them 4.______
(monomers) link together in the setting or curing process to form chains
(polymers), which give plastics their flexible strength. Some plastics retain
their ability to be softened and reshaped; as wax, they are thermoplastic. 5.______
Others set permanently in the shapes they are given by heat and pressure;
like bags, they are thermosetting.
From industrial beginnings in nineteenth century, plastics have 6.______
struggled through a hundred and twenty years of glory, failure, disrepute
and suspicion on the slow road to public acceptance. Now, at last, one can
positively say that plastics are appreciated and enjoyed for what they are;
that they make modern life rich, more comfortable and convenient, and 7.______
also more fun. Plastics are warm materials, sympathetic with the human 8.______
touch, and their transformation into things that come into contact with human
beings is entirely appropriate.
The fact there are plastic antiques comes as a shock to most people. 9.______
How can a material that seems so essentially twentieth century, and one
that is so much associated with cheap, disposed products, has a history 10.______
at all? It is a young technology, and a great part of the fun of collecting
plastics is that beautiful pieces of historical interest can still be found very
cheaply.
选项
答案
last——lasting
解析
本题为形容词误用。last表示“最后的”但此处并没有强调先后;lasting表示“永久的,持久的”指塑料的定型。
转载请注明原文地址:https://kaotiyun.com/show/mcYO777K
0
专业英语八级
相关试题推荐
LeacockwasprobablythefirstCanadiantoqualifyasa"pro-AmericanBritishimperialist."Acolleague,Prof.JohnCulliton,sa
TerritorialExpansionoftheUnitedStatesTerritoryDateAcquiredSquareMilesHowAcquiredOriginalstatesandterritories
DiscussionoftheassimilationofPuertoRicansintheUnitedStateshasfocusedontwofactors:socialstandingandthelossof
Countriesatalllevelsofeconomicdevelopmentfaceasimilarchallenge:tomaketheirindustriescompetitiveinanincreasingl
AMarxistsociologisthasarguedthatracismstemsfromtheclassstrugglethatisuniquetothecapitalistsystemmthatracial
WHO,workingcloselywithitsMemberStates,otherUnitedNationsagenciesandnongovernmentalorganizations,isfocusingonma
TheOpenUniversitywasestablishedin1969toprovidedegreecoursesincorrespondenceforstudentsof21yearsandover,
Whilethepercentageofurbanresidentsishigherinrelativelydevelopedcountries,developingcountrieshaveanincreasingnum
Somepeoplebelievethatinternationalsportcreatesgoodwillbetweenthenationsandthatifcountriesplaygamestogetherthey
Pyramidsarelargestructureswithsquarebasesandfoursmooth,triangular-shapedsidesthatcometoapointatthetop.Severa
随机试题
患者咳嗽,查体:气管向左偏移。右侧胸廓较左侧饱满,叩诊出现鼓音。应首先考虑的是()
石膏与知母均能治疗的病证是
表干法测定马歇尔试件毛体积密度的温度可以为()。
质押债券的保证物是()。
个人一手房贷款和二手房贷款的期限由银行根据实际情况合理确定,最长期限都为30年。()
施工企业的应收账款主要表现为()。
急慢性传染病的防治与管理、计划免疫的接种、疾病监测的开展、劳动卫生的监测、职业病及肿瘤、心脑血管病的防治等服务属于社区卫生服务中的( )。
以下叙述正确的是()。
智力测验所测量的是()。
《开罗宣言》
最新回复
(
0
)