Grammar for Science, Technology: Prefixes, Measurements

2024-05-31

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1
  • What do news stories about space travel, technology, or energy production have in common?
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  • Well, one way to answer this question is to look at special prefixes that are often used with measurements in science and industry.
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  • These prefixes are especially important to people studying in the STEM fields of science, technology, engineering, and math.
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  • Let's start with some important terms and ideas.
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  • Prefixes are additions to the beginnings of words.
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  • When we add a prefix to a word, it changes the meaning of the existing word, and the result is a new word.
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  • Let's take an example to clarify the point. We have the prefix "un-," meaning not.
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  • Then we have the full word "happy."
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  • When we add the prefix "un-" to the beginning of the word "happy," we get the word "unhappy."
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  • There are many kinds of prefixes.
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  • For today's lesson, we will pay attention to one kind of prefix: prefixes related to large amounts.
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  • The National Institute of Standards and Technology (NIST) is a U.S government agency that works on measurement science.
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  • NIST has a public list of prefixes used for amounts, or quantities, and their meanings.
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  • The list is long. But there are only a few of these prefixes that are important for everyday uses in the sciences and industry.
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  • The prefixes that mean one thousand, one million, one billion, and one trillion are useful to know for most kinds of science, energy, and technology stories.
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  • Here is how NIST defines these prefixes:
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  • Kilo- means thousand.
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  • Mega- means million.
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  • Giga- means billion.
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  • Tera- means trillion.
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  • In science and industry, we often use large number prefixes to express measurements of distance, energy, or weight.
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  • An example of a distance measurement is a meter.
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  • An example of a power measurement is a watt.
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  • Let's take an example that everyone knows: one kilometer.
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  • We have the prefix kilo-, meaning one thousand, and the unit of distance, a meter.
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  • Let's listen to how Bryan Lynn uses the term "kilometer" in a recent science story on our website:
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  • NASA estimates the moon sits an average of about 382,500 kilometers from Earth.
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  • The exact distance changes because of the moon's orbit around Earth.
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  • The average distance from Earth to Mars is 225 million kilometers.
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  • Our example shows an important point about agreement.
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  • Note that in our example, we make the measurement of distance plural.
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  • We add an -s to the end of kilometer, and so we get the term "kilometers."
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  • So, we say one kilometer, two kilometers, and 300,000 kilometers.
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  • The idea is that the prefix changes the meaning of the word, but the word must still agree in terms of being singular or plural.
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  • So, do not forget about the plural markers we use at the ends of words.
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  • We can carry this same idea to an energy story.
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  • A watt is a unit of power.
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  • When we use prefixes to change the meaning, we arrive at a term such as a megawatt - meaning a million watts - or a gigawatt - meaning a billion watts.
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  • Let's listen to part of a recent report about wind energy development in 2023.
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  • The Global Wind Report, published recently by the Global Wind Energy Council (GWEC), a trade group, said the world developed 117 gigawatts of new wind power capacity, a 50 percent increase from 2022.
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  • Note that in our example, the power capacity measurement is expressed in gigawatts.
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  • Once again, we add the -s ending to gigawatt because it is plural: 117 gigawatts.
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  • Let's take some time to work with these ideas.
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  • Imagine you want to describe the amount of data that a hard drive can hold.
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  • Use the prefix "tera-" and the unit of computer information, a byte, to describe the storage capacity of the hard drive.
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  • Pause the audio to consider your answer.
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  • Here is one possible answer:
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  • This hard drive has one terabyte of data storage capacity.
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  • Here is another possible answer:
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  • This hard drive has two terabytes of data storage capacity.
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  • We will end this Everyday Grammar with a call to action.
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  • Write us a short description of something related to science, energy, or technology.
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  • Be sure to use prefixes such as kilo-, mega-, giga-, or tera-.
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  • Try to connect your description to something related to your country or your life.
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  • You can write us your answers in an email to learningenglish@voanews.com
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  • In a future Everyday Grammar, we will give feedback on some of the messages we receive.
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  • I'm John Russell.