[英语]提高听力，打牢基础的利器(6)

　　值得注意的是，读音清晰与否对听力理解影响也很大。以新概念各录音版本为例，外研社是语速最慢发音最清晰的，几乎无连读弱读。世界图书出版公司引进的朗文原版录音语速与上海外教语速差不多，朗文是BBC播音员朗读，发音非常漂亮，适当省音连读，上外男声省音连读弱读非常多。如果想提高听力，建议选用难度大的材料进步才快。

　　以baobab为例， 新概念4的后几十课都听写世图版, 看看正确率一直都不错, 还以为自己听力突飞猛进呢, 没想到有天听写上外版大受打击, 实在听不出了换上世图版就听写出来了, 看看还都听写到五十多课了, 非常后悔前面几十课没有听写上外版的录音。所以单纯从错误率来判断听力进度是片面的。

　　下面以baobab当初学习上外版新概念4错误率最高的与错误率最低的两篇听写记录为例，从以下两篇听写记录可看出,<<新概念4>>的25,26课, 篇幅,难度,生词数量差不多 , 差别只在于语速。 若我没计算语速, 就会被单纯的"听写错误率"所蒙蔽, 而沾沾自喜, 以为听力在一夜之间“突飞猛进”：

     《新概念4》学习实录：黑体字为未听懂的原文，括弧内为错误的

　　学习记录一:

　　lesson 25 ：The snake

　　听写文本

　　How it came about that snakes manufactured poison is a mystery. Over the periods their（they are） saliva, a(and) mild, digestive juice like our own, was converted into a poison that defies analysis even today. It was not forced (the first) upon them by the survival competition; they could have caught and lived on prey without using poison just as the thousands of non-poisonous snakes still do. Poison to a snake is merely a luxury; it enables it to get (together) its food with very little(low) effort, no more effort than one bite. And why only snakes ? Cats(catch), for instance, would be greatly helped; no running fights(fight) with large, fierce rats or tussles(tussle) with grown rabbits-just a bite and no more effort needed. In fact it would(will) be an assistance(a system) to all the carnivorae--though it would be a two-edged weapon -When they fought eachother. But, of(in) the vertebrates, unpredictable Nature selected only snakes (and one lizard). One wonders also why Nature, with(were) some snakes concocted poison of such extreme potency.

　　In the conversion of saliva into poison one might suppose that a fixed process took place(to place). It did not; some snakes manufactured(manufacture) a(the) poison different in every respect from that of others, as different as arsenic is from （other snakes to）trychnine, and having different effects. One poison acts on the nerves, the other on the blood.

　　The makers(make) of the nerve poison include the mambas and the cobras and their venom is called neurotoxic.Vipers (adders) and rattlesnakes manufacture the blood poison, which is known as haemolytic. Both poisons are unpleasant, but by far the more unpleasant is the blood poison. It is said that the nerve poison

　　is the more primitive of the two, that the blood poison is , so to speak, a newer(newl) product from an improved formula. Be that as it may(lead that as it may), the nerve poison does its business(experience) with man far more quickly than the blood poison. This,however,means nothing.Snakes did not acquire(aquire) their poison for use against man but for use against prey(preys) such as rats and mice, and the effects on these of viperine poison is almost immediate.