写作金属材料中的每一词与它其间的词汇或语句即使章节都有著密切的亲密关系，他们能借助情境和各式各样未知重要信息推断、推论这类背单字的字义。许多这时候，揣测忤逆、模糊不清掌控单字涵义，不仅不负面影响他们的写作，反倒会提升写作速率和产品质量。推论三个单字的原意不仅有赖于语句，所以还须要把语句放到语句中，透过语句提供更多的准则去认知。假如实际上是孤立无援的一句话就极难揣测。在三个脚注里，或极短的语句中，他们能用下列方式来揣测。

1.代名词准则

I did not have a roll on my plate, but I do not like bread very much anyway。

从语句的后半部份能窥见，骂人人不讨厌奶油，由此可见roll也是一类奶油。透过bread那个词，能猜到roll的字义。

One night Mrs Rochester succeeded in setting the house on fire. Mr Rochester managed to lead the servants to safety and then went back into the burning mansion to rescue his wife。

第三个语句中的mansion是背单字。从其间三个语句上看，他们无从辨认出mansion指的是第二句中的house。

2.自然环境准则

We are glad that we live near the ocean because we love to eat flounder。

假如单从他们香甜可口flounder该些，难以推论它的原意，而后面提及the ocean，则能推论出flounder是一类鱼种或海产品。

She read my letter slowly to the end and then tore it to shreds。

那个语句中的shreds是背单字。但他们从多音节来认知，她慢慢地把我的信看完，接着把它劈成……，从劈成……，他们能猜到shreds是碎块的原意。

3.商业用途准则

We like our new house because it has a few elms in the back yard that will give us shade and keep the house cooler。

透过elms的作用，能有阴凉使房屋凉爽些，他们能揣测出elms是一类树。

Fishes live in water and have fins which help them to swim。

运用生活常识就能较为确切地推论出fins的字义是鳍。

4.因果亲密关系准则

She can’t play tennis now because she can’t find her white sneakers。

由于找不到那个白色的sneakers，所以难以打网球。由此可见sneakers是一类和打网球有关的东西。而从white和sneakers那个词的复数形式看，你也许已经猜到它们原意是球鞋了。

The lack of movement caused the muscles to weaken. Sometimes the weakness was permanent. So the player could never play the sport again。

从后面的结果永远不能再运动中，能推断出 permanent的原意是永久的。

5.对比准则

She is usually prompt for all her classes, but today she arrived in the middle of her first class。

but表示原意的转折，因此能窥见but其间的原意是相反的。后半句说，她今天在第一节课上了一半时才来。反推回去，她平时应该是一向准时的了。

The pain on the cottage had peeled in a few places, otherwise they looked well kept。

句中peel可从otherwise后面的对比猜到是脱落之意。

6.说明准则

Ann is very smart. She always knows the answers to all the teachers’questions。

第二句是对前一句的补充说明。三个能回答老师所有问题的女孩，Ann一定是很聪明的。

Capacitance, or the ability to store electric charge, is one of the most common characteristics of electronic circuits。

由后半句的解释他们很快猜到背单字capacitance字义——电容量。

7.顺序准则

After Ms Ellis put the letters in the envelope, she sealed it and put a stamp on it。

在发信时，先把信装入信封，封上口，接着贴上邮票，是合理的顺序，透过其间动作，无从窥见seal是封口的原意。

接下来他们再做个练习，请看下面的脚注：

After we had travelled for about twenty miles, there was still no sign of the town which was marked on the map. We were beginning to get worried. Then, without warning, the car stopped. A quick examination showed that we had run out of petrol. Although we had little food with us, only a few biscuits and some chocolate, we decided to spend the night in the car。

这一段中，假设petrol和biscuit三个词是背单字，但他们能从语句的其间文中推断出这三个词的原意。如文中提及汽车在没有任何出毛病的先兆时就突然停了，文中又有run our of——用完那个词组，因此能推断出一定是汽油用完了，从而petrol的原意即可推断出。下边的biscuit是背单字，但这一句的前半句提及了 we had little food with us, biscuit和chocolate都是进一步补充说明是什么样的food，由此由此可见，这两样东西是食品。这时他们已经明白了大致的原意，不查词典，也不妨碍他们认知文章的原意。因此，就能继续读下去，有时读到后面，又会辨认出后面出现的背单字的原意在后面有了解释。