The difference between a liquid and a gas is obvious 【C1】______the conditions of temperature and pressure 【C2】______found at the

admin2012-03-21  29

问题     The difference between a liquid and a gas is obvious 【C1】______the conditions of temperature and pressure 【C2】______found at the surface of the Earth. A liquid can be kept in an open container and 【C3】______ it to the level of a free surface. A gas forms no free surface but 【C4】______to diffuse throughout the space available; it must 【C5】______be kept in a closed container, as 【C6】______a planet’s atmosphere. The distinction was a prominent feature of early theories 【C7】______the phases of matter. In the nineteenth century, for example, one theory 【C8】______that a liquid could be "dissolved" in a vapor without losing its 【C9】______, and another theory held that the two phases are 【C10】______different kinds of molecules (分子). The theories now prevailing 【C11】______a quite different approach by emphasizing what liquids and gases have in common. They are both forms of matter that have no 【C12】______structure, and they both flow easily. They are fluids.
    The 【C13】______similarity of liquids and gases becomes clearly apparent when the temperature and pressure are raised somewhat. 【C14】______a closed container partially filled with a liquid is heated. The liquid expands, or 【C15】______, becomes less dense; some of it evaporates. 【C16】______, the vapor above the liquid surface becomes denser 【C17】______the evaporated molecules are added to it. The combination of temperature and pressure 【C18】______the densities become equal is 【C19】______the critical point. Above the critical point the liquid and the gas can no longer be 【C20】_____; there is a single, undifferentiated fluid phase of uniform density.
【C15】

选项 A、in a word
B、in the meantime
C、in other words
D、in that case

答案C

解析 介词词组。in aword是“总之,一句话”的意思,in the meantime是“同时”的意思,in other words是“换句话说”的意思,in that case表示“那样的话”。根据上下文,液体扩散其实就是它的密度变小了,所以这里应选择C.
转载请注明原文地址:https://kaotiyun.com/show/zzmK777K
0

最新回复(0)