首页
登录
职称英语
The difference between a liquid and a gas is obvious【46】______the conditions
The difference between a liquid and a gas is obvious【46】______the conditions
游客
2023-10-13
0
管理
问题
The difference between a liquid and a gas is obvious【46】______the conditions of temperature and pressure commonly found at the surface of the Earth. A liquid can be kept in an open container and fills it to the level of a free surface. A gas forms no free surface but tends to diffuse throughout the space available; it must【47】______be kept in a closed container, as in the【48】______of a planet’ s atmosphere. The distinction was a prominent feature of early theories【49】______(describe) the phases of matter. In the nineteenth century, for example, one theory maintained that a liquid could be "dissolved" in a vapor without losing its identity, and another theory held that the two phases are made up of different kinds of molecules (分子). The theories now prevailing【50】 t______a quite different approach by emphasizing what liquids and gases have in common. They are both forms of matter【51】______have no permanent structure , and they both flow easily. They are fluids.
The【52】______(fundament) similarity of liquids and gases becomes clearly apparent when the temperature and pressure are raised somewhat. Suppose a closed container partially filled with a liquid is heated. The liquid expands, or in other【53】______, becomes less dense; some of it evaporates. In contrast, the vapor above the liquid surface becomes dense as the evaporated molecules are added to it. The combination of temperature and pressure【54】______ which the densities become equal is called the critical point. Above the critical point the liquid and the gas can no longer be【55】______(distinguish) ; there is a single, undifferentiated fluid phase of uniform density. [br]
选项
答案
describing
解析
本句中的describe的逻辑主语为theories,故应用现在分词。同时,describe这一动作只说明一种事实,并不与其他动词作时间上的先后比较,不必用 完成时。
转载请注明原文地址:https://tihaiku.com/zcyy/3095444.html
相关试题推荐
Acollisionbetweenanaircraftandoneormorebirdsistermedabird-strik
Acollisionbetweenanaircraftandoneormorebirdsistermedabird-strik
Acollisionbetweenanaircraftandoneormorebirdsistermedabird-strik
Acollisionbetweenanaircraftandoneormorebirdsistermedabird-strik
It’snotliquid,gasorsolid.It’snotananimal,aplantoramineral.It’s
In1908,thefirstinternationalrugbymatchwas________inParisbetweenFrance
Inaddition,therearetoomuchregionaldifferencesinvocabularyforthelangu
Thereisabigdifferencebetweentownlifeand【D1】__________inEngland.
Thereisabigdifferencebetweentownlifeand【D1】__________inEngland.
Thereisabigdifferencebetweentownlifeand【D1】__________inEngland.
随机试题
足球运动员的()视野范围比一般人大A.红色 B.白色 C.黄色 D.绿色
成组设计的方差分析中,若处理因素无作用,则理论上A.F<1 B.F=1 C.
鼻内镜手术操作在中鼻甲内侧进行易A.损伤筛前动脉引起鼻出血 B.损伤筛板出现脑
Thechangeinthatvillagewasmiraculou
第三度房室传导阻滞临床症状可取决于A.心室率的快慢 B.心房率的快慢 C.心
A. B.升高温度,使v(逆)增大,v(正)减小,将导致平衡向左移动 C.加
人在每一瞬间,将心理活动选择了某些对象而忽略了另一些对象。这一特点指的是注意的(
抗结核药物中,全杀菌药是A.卡那霉素 B.链霉素 C.吡嗪酰胺 D.异烟肼
不用于解救重金属中毒的是A.二巯丙醇 B.二巯丁二钠 C.依地酸钙钠 D.
土质改良是防治管涌与流沙(土)的基本措施之一,常用的方法有( )。A.注浆法
最新回复
(
0
)