By contrast, in the United States an estimated 97 million birds are killed each year when they collide with buildings made of plate glass, 57 million are killed on highways each year; at least 3.8 million die annually from pollution and poisoning; and millions of birds are electrocuted each year by transmission and distribution lines carrying power produced by nuclear and coal power plants.这个句子真是长，见到这个长句的时候，我都有些生气了，怎么能写这么长呢？但为了练习长句理解能力，只能硬着头皮读完。
心中默念不要浮躁，先读完再说，万一不是很难呢。
结果读完，嘿，真的不难，居然一遍就明白其意思，只要会断句，那就理解起来非常easy。
in the United States an estimated 97 million birds are killed each year when they collide with buildings made of plate glass, 57 million are killed on highways each year; 这句话已经很长了，必须断开，就断在when前面的位置，然后是57million前面的逗号地方断开，然后是分号的地方也断开。
in the United States（在美国）an estimated 97 million birds are killed each year （每年大约有97M鸟死亡）when they collide with buildings made of plate glass, （当这些鸟撞到玻璃建筑的时候）57 million are killed on highways each year; （每年57M的鸟死于高速公路）at least 3.8 million die annually from pollution and poisoning;（每年至少3.8M的鸟死于污染和中毒）and millions of birds are electrocuted each year （每年有成千上万的鸟触电身亡）by transmission and distribution lines carrying power （电力输送）produced by nuclear and coal power plants（核电站和煤电站发出的电）collide是撞击的意思；electrocuted 是触电的意思。
这个句子能看懂意思，我觉得做托福阅读的时候真的就是信心大涨，但是如果要翻译好这个句子的话，我真的是很难做到啊。