内容简介
听众 Tony 来信询问易混词 “maximum” 和 “maximal” 以及 “optimum” 和 “optimal” 之间的区别。这四个词都可以作形容词使用。“Maximum” 和 “maximal” 的意思都包含 “最高的”；“optimum” 和 “optimal” 的意思都包含 “最佳的”，这也正是它们让人困惑的地方。本期节目将一一讲解它们的用法及区别。
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（关于台词的备注: 请注意这不是广播节目的逐字稿件。本文稿可能没有体现录制、编辑过程中对节目做出的改变。）
Jiaying 大家好，欢迎收听 BBC英语教学的 “你问我答” 节目。I'm Jiaying.
Phil And I'm Phil, welcome!
Jiaying 本期节目要回答的问题来自听众 Tony，问题由我来代读：
Question Hi, my name is Tony from Shenzhen, China. I have a question for you. Could you please help explain the difference between 'maximum' and 'maximal', and between 'optimum' and 'optimal'?
Phil OK, so we've got two pairs of words – and the words in each pair are closely related. It's a great question because it's very easy to confuse them.
Jiaying 是的，问题中的单词可以被分为两组：第一组是 “maximum” 和 “maximal”；第二组是 “optimum” 和 “optimal”。先来看第一组单词 “maximum” 和 “maximal”。
Phil Why not? OK. Both 'maximum' and 'maximal' are about something being the highest or largest number or quantity.
Jiaying 是的，这两个词都和 “事物的最大数量或数值” 有关，但它们的区别在于用法和所使用的语境不同。
Phil So, the thing to remember is that 'maximal' is only used as an adjective, and is only commonly used in scientific language.
Jiaying 要记住：“maximal” 只能作形容词，意思是 “最多的，最大的，最高的”，而且它通常只在谈论科学的语境中才常用。听两个例句。
Examples The patient's maximal heart rate is 170 beats per minute.
The maximal temperature for safe storage is 25 degrees.
Jiaying 再来看 “maximum”。“Maximum” 常作形容词使用，意思也是 “最多的，最大的，最高的”；它还可以作名词使用，意思是 “最大限度，最大值”。在非正式的语境中，它甚至可以作副词。“Maximum” 的用法并不局限于科学领域，它可以用来谈论多种不同的事物，而且比形容词 “maximal” 要更常用。听三个例句。
Examples I'm not sure this hall is big enough for all our guests. They said that 50 is the maximum.
The maximum speed that you can drive at on the motorway is 110 kilometres per hour.
I'm only going to work maximum five hours today.
Phil Now, let's look at 'optimum' and 'optimal' – these words are often used in the same way and mean the same as 'best'.
Jiaying “Optimum” 和 “optimal” 的相同点是两者都可以作形容词，表示 “最佳的，最优的”。听两个例句。
Examples 150 minutes per week is the optimum amount of time to spend exercising.
This idea is the cheapest, so I think it's the optimal solution.
Phil Now, here's the difference: it's less common, but we can use 'optimum' as a noun. 'Optimal' can't be used in this way.
Jiaying 是的，“optimum” 和 “optimal” 之间的区别是：“optimum” 还可以作名词使用，指 “最佳效果、状态，最适宜条件”，而 “optimal” 则没有这个用法。注意：“optimum” 的名词用法并没有它的形容词用法常见。听两个例句。
Examples This chemical reaction reaches its optimum at 35 degrees.
During the summer months, the plant's growth is at its optimum.
Jiaying 好了，大家可以这样记忆问题中四个词之间的主要区别：“maximal” 和 “optimal” 只能作形容词使用；而 “maximum” 和 “optimum” 的词性则不局限于形容词，而且用法相对灵活。
Phil Don't forget that 'maximal' is only really used in scientific language, while it's not that common to use 'optimum' as a noun.
Remember that if you have a question you'd like us to answer, you can email us too at: questions.chinaelt@bbc.co.uk
Jiaying 你也可以把问题通过微博私信的方式发给我们，我们的微博账号是 “BBC英语教学 ”。谢谢收听本期 “你问我答” 节目。Bye, everyone!
Phil Bye.
