Ordinary meteoric water is water that has soaked into the ground from the surface, from precipitation (rain and snow) and from lakes and streams.
托福阅读文章句子成分剖析：Ordinary meteoric water是句子的主语，is是系动词，that引导的的定语从句修饰water，并在定语从句中做主语，has soaked谓语。
For example, as the great ice sheets that covered North America during the last ice age steadily melted away, huge volumes of water flowed from them.
As引导时间状语从句，the great ice sheets 是从句的主语，that引导定语从句并作从句的主语修饰the great ice sheets，melted away从句的谓语。Huge volumes of water是主句的主语，flowed是主句的谓语。
In that case, climax communities would be the most fragile and the least stable, since they can require hundreds of years to return to the climax state.
托福阅读高分方案句子成分剖析：In that case介词短语作状语，climax communities句子的主语，would be谓语动词，since表缘由。
It has long been accepted that the Americas were colonized by a migration of peoples from Asia, slowly traveling across a land bridge called Beringia (now the Bering Strait between northeastern Asia and Alaska) during the last Ice Age.
Only the last of these was suited at all to the continuous operating of machines, and although waterpower abounded in Lancashire and Scotland and ran grain mills as well as textile mills, it had one great disadvantage：streams flowed where nature intended them to and water-driven factories had to be located on their banks whether or not the location was desirable for other reasons.
Early in the century, a pump had come into use in which expanding steam raised a piston in a cylinder, and atmospheric pressure brought it down again when the steam condensed inside the cylinder to form a vacuum.
句子成分剖析：early in the century是时间状语，and连接两个并列句