The destruction of habitats(栖息地)all over the world is the primary reason species are?becoming extinct(灭绝)or endangered．Houses,highways,dams,industrial buildings,and?ever-spreading farms now dominate?21?formerly occupied by forests,deserts,and wetlands．22?the beginning of European settlement in America,23,
over 65,000,000 acres of?wetlands have been drained．One million acres alone vanished
24?1985 and 1995．
Habitat destruction can be?25?or it can be subtle,occurring over a
26?period of time?without being noticed．27?such as sewage from cities and chemical runoff fromfarms,can change?the?28?and quantity of water in streams and rivers．To?29?living in a delicately balanced?habitat,this disturbance can be as
30?as the clear-cutting of a rainforest．
31?remaining habitats are carved into smaller and smaller pockets or islands,remaining?species are forced to exist in these?32?areas,which causes further habitat?33?These?species become less adaptable to environmental?34；in fact,they become?35?endangered．Scientists believe that when a habitat is cut by 90%,one-half of its plants,animals and insects will?become extinct．
第22题的答案是（ ）
A、At
B、Before
C、After
D、Since
【正确答案】：C
【题目解析】：第22题考查的是时间状语的选择。根据原文，“over 65,000,000 acres of wetlands have been drained”是一个完成的动作，表示湿地被排干是一个已发生的事实。而紧接着的句子“One million acres alone vanished between 1985 and 1995”则给出了一个具体的时间段，说明湿地消失的速度和程度。
要确定第22题答案，我们需要分析句子“22 the beginning of European settlement in America,23, over 65,000,000 acres of wetlands have been drained”中的时间关系。这里的关键信息是“over 65,000,000 acres of wetlands have been drained”，即“超过6500万英亩的湿地已经被排干”，这是一个已经完成的动作。因此，我们需要找到一个表示“在……之后”的时间状语。
选项A "At" 通常用于表示具体的时间点或瞬间，不符合此处表示一段时间后的语境；
选项B "Before" 表示“在……之前”，与文意不符；
选项C "After" 表示“在……之后”，符合语境；
选项D "Since" 通常用于表示从某一时间点开始到现在的时间段，但这里需要的是表示某个动作发生后的时间状语，因此也不适用。
因此，正确答案是C，“After”，表示在欧洲人定居美洲之后，超过6500万英亩的湿地已经被排干。这反映了栖息地破坏的严重性和对物种生存的影响。
The destruction of habitats(栖息地)all over the world is the primar
- 2024-11-09 06:41:28
- 英语（专升本）