Ⅲ. 句式填空1. -ing 分词作状语和定语Looking ahead (展望未来) , scientists believe that global warming could be one of the biggest environmental problems facing the 21st century ( 21 世纪所面临的) . 2. It seems that. . . 句型“似乎……,好像……”Given this data, it seems that ( 好像 )the link between human activities and rising global temperatures is not merely a coincidence. 3. 条件状语从句的省略If necessary ( 如果有必要的话 ), give reasons for your answers. 4. not only. . . but (also). . . 不但……而且……Rivers, lakes, and wet-lands are sources of fresh water, not only ( 不但 )for humans, but ( 而且 ) for wildlife as well. Ⅳ. 教材设题1. The water level has risen ______ high in several places ______ many homes are at risk from flooding. A. so; that B. such; thatC. so; as to D. such; as to 【解析】选 A 。本句中的 high 为形容词,需要用副词修饰,而 so. . . that 句型中, so 为副词,修饰形容词,故 A 项正确。 2. Which countries do you think _______ more to global warming? A. adapt B. belong C. relate D. contribute【解析】选 D 。 contribute to. . . 为固定短语,此处表示“导致,在……方面起作用”的意思,其他不合题意。 3. Global warming is _______ due to human activities. A. most B. mostly C. nearly D. almost【解析】选 B 。 mostly 用作副词,意为“主要地,大部分地”。此处指全球变暖主要是由人类活动引起的。 4. Because these natural disasters _____ at random times, it is difficult to warn people ______ . A. occur; in advance B. take place; beforehandC. break out; ahead of time D. occur; in advance of it【解析】选 A 。 occur 表示“发生”,强调“出乎意料”;take place 强调“按照事前的计划或安排而发生”; break out 强调“战争、火灾等”的突然爆发;由此可排除 B 项和 C项。根据句意:由于这些自然灾害不定时地发生,所以很难提前警告人们。故 A ...