有时短文中出现一个需要猜测其意义的词或短语，下面接着出现其定义或解释。标点符号，如逗号后的解释(名词同位语)、破折号后的解释、括号内的解释等。这都是判断该词或短语意义的主要依据。例如：
①Annealing is a way of making metal softer by heating it and then letting it cool very slowly.
句子给予了annealing一个明确的定义，即“退火”。
②It will be very hard but also very brittle — that is, it will break easily.
从that is(也就是说)后的解释中我们可以了解到，brittle是“脆的”意思。
③The herdsman,_who looks after sheep, earns about 650 yuan a year.
定语从句中looks after sheep就表明了herdsman的词义为“牧人”。
④The weather in this area is treacherous;_its sudden changes often endanger the lives of sailors.
分号后的句子在解释什么样的天气是treacherous, sudden change与treacherous在语义上相对应，因此含义是“突变的”。
⑤Some good readers find it helpful to use their sense to visualize — or picture — what they read.
visualize的意思由破折号后的picture(想象)给出了说明，因此含义为“想象”。
⑥When President Torrijos of Panama met Carter, he tried to give him a friendly abrazo (hug)．
abrazo对大多数人来说都很陌生，但由括号内的hug(拥抱)，我们不难推测abrazo也是“拥抱”的意思。
[例] (2018·全国卷Ⅰ阅读C节选)
Soon afterwards, many of those people started settling down to become farmers, and their languages too became more settled and fewer in number. In recent centuries, trade, industrialisation, the development of the nationstate and the spread of universal compulsory education, especially globalisation and better communications in the past few decades, all have caused many languages to disappear, and dominant languages such as English, Spanish and Chinese are increasingly taking over.
29．Which of the following best explains “dominant” underlined in paragraph 2?
A．Complex. B．Advanced.
C．Powerful. D．Modern.
[分析] 根据画线词所在句子可知，人类社会发展的很多因素导致许多语言消失，而逐渐被英语、西班牙语、汉语等语言取代，画线词前后的解释暗示了这些语言逐渐占主导地位，故选C项powerful (强大的，有影响力的)。
阅读中出现的难词有时后面紧跟一个同位语，对前面的词进行解释，因此可利用同位关系对前面的词义或句意进行猜测。例如：
①They traveled a long way, at last got to a castle,_a large building in old times.
同位语部分“a large building in old times”给出了castle的确切词义，即古时候的“城堡”。
②We are on the night_shift — from midnight to 8 a．m. — this week.
两个破折号之间的短语很清楚地表明night shift是“夜班”的意思。
③The “Chunnel”， a tunnel (隧道) connecting England and France, is now complete.
此句中“a tunnel (隧道) connecting England and France”是Chunnel的同位语。因此，Chunnel指的就是英法之间的海底隧道。
