When to (and When Not to) Use Capital Letters in English? Part 1

First, let’s get the obvious things out of the way. Everybody knows that we use capital letters for:

1. The first word of a sentence or a line of poetry
2. The pronoun “I” regardless of its position in the sentence**
3. Names**

*This is not the case in (many/any) other languages. In other languages, it’s possible to see the pronoun “you” (singular) capitalized because it’s a polite form. As for the English I, it is not clear if there are any records as to when and why the practice of capitalizing it began, but rumor has it that it is mainly because a lower case i is difficult to read.

**Many things around us have names. That is why this list is so long.

By the way, it is worth mentioning that rules on capitalization vary from language to language, so depending on your learners’ native language, some of these rules may not be as easy or as obvious as they seem. Not to mention that many languages don’t even have capital letters. (For example, Indic languages, Korean, Arabic, etc.)

Ok, let’s begin.

If the image below appears to be broken, click on the link at the bottom of it to open it.

Capital Letters 1 – Color Legend by Meri Zaha

If you cannot find what you are looking for in the Table of Contents below, check out the “When to (and When Not to) Use Capital Letters in English? Part 2” & “When to (and When Not to) Use Capital Letters in English? Part 3” posts. (Open in a new tab.)

We always use capital letters for proper nouns. A proper noun is a noun that refers to a single specific entity, while a common noun stands for a group of similar entities. Therefore, we use a capital letter for France because it is a proper noun, but not for the noun country because it is a common noun.

1. People and animals 👩‍🦱 🐕

The names of people and animals are proper nouns, so they need a capital letter.

• I gave my book to David.
• My cat Oreo is playing with his toy-mouse Jery.*

*If you happened to name your cat’s toy, it gets a capital letter too.

By the way, this goes for all the (nick)names a person or an animal may have, even if they are hyphenated.

For example, Catherine Zeta-Jones.

1.1 A note on animals 🦓

Generally, we do not use capital letters for animals.

• The zebra‘s skin is black; only its fur is striped.
• Did you know that the largest animal in the world is the blue whale?

If the image below appears to be broken, click on the link at the bottom of it to open it.

National Geographic – Mountain Lion by Meri Zaha

However, there are some exceptions.

If part of the name is a proper adjective, we capitalize that part. Proper adjectives are very common in different cat and dog breeds.

• My dog is a German shepherd mix.
• What is the difference between African and Indian elephants?

In the examples above, the words German, African and Indian are proper adjectives. They are called that because they are derived from proper nouns. In this case, the names of two countries and a continent. A proper adjective may also be derived from people’s names: Victoria – Victorian. The point is that proper adjectives are always capitalized. 🙂

In the case below, we capitalize both words Great and Dane because the whole phrase is a proper noun. Great Dane, as a phrase, refers to a specific dog breed.

Scooby-Doo is a Great Dane who helps solve a lot of mysteries.

Consider this:

• He is such a gentle giant: a typical Great Dane.*
• He is such a gentle giant: a typical great Dane.**

*Refers to the specific dog breed.
**Is either a mistake or, if not, refers to a great person of Danish descent. Could it be Hans Christian Andersen? Maybe but he wasn’t famous for being a gentle giant so, maybe not. Then again, Great Danes are known for being gentle giants if trained and raised right. 🙂

2. Plants and foods

Generally, plants and foods do not need capital letters. However, if the name is a brand name or trademark, or includes a proper noun/ adjective, then that part needs a capital letter.

If the image below appears to be broken, click on the link at the bottom of it to open it.

Capital letters for different foods and plants by Meri Zaha

3. Planets 🪐

We use capital letters for planets. Planets have been named, so their names are capitalized.

• Saturn is the second-largest planet, and the biggest one is Jupiter.
• Mercury is the closest planet to the Sun.

3.1 The Sun and the Moon* ☀🌙

Speaking of the Sun in the example above, note the words sun, earth, and moon! They are quite special.

Capitalize “Moon” when referring to Earth’s Moon; otherwise, lowercase “moon”. Capitalize “Sun” when referring to our Sun but not to other suns… When “earth” is lowercased, it refers to soil or the ground, not the planet as a whole.

Style Guide for NASA History Authors and Editors

Here are some examples to illustrate the difference:

• It takes six to eight months to travel from Earth to Mars.
• The archaeologists excavated the earth at the site.
• Several planets have moons. Are all moons as big as the Moon?
• The little girl has been playing in the sun all day.
• The temperature at the surface of the Sun is over 5000°C.

Obviously, due to the extremely high temperatures, it would be impossible for the little girl to be playing in the Sun all day, wouldn’t it?

3.2 Solar system and universe 🌌

If you do a Google search on whether or not you should capitalize solar system, you will probably end up wondering what to do. According to some sources, when referring to our solar system you should use capital letters, just like you would do with Earth when referring to our planet. The reasoning is the same – there are many solar systems (common noun) but, when referring to our one and only Solar System (proper noun), we must use capital letters. (The Solar System Wikipedia page does exactly that.)

Let’s see, however, what NASA’s guide quoted above about the Sun, the Moon, and planet Earth, has to say about it:

Do not capitalize “solar system” and “universe.”

Style Guide for NASA History Authors and Editors

In the example below from the article “What is an Exoplanet?” we will find that NASA uses lower case letters for both the universe and the solar system, even when referring to our solar system.

If the image below appears to be broken, click on the link at the bottom of it to open it.

NASA – Universe & solar system by Meri Zaha

Last but not least, Stephen Hawking, a man who knew a lot about the universe, does the same in his book Brief Answers to the Big Questions.

“The universe would have existed forever, and would have looked the same at all times.” & “Our own solar system was formed about four and a half billion years ago…” — Stephen Hawking, Brief Answers to the Big Questions, p. 47 & p. 73

For both, the universe and the solar system, Stephen Hawking uses lower case, not upper case, even though he, too, refers to our solar system.

I guess there is no debate as to whether or not we capitalize the event which, according to science, and the book cited here, was the beginning of everything. 🙂

4. Compass points* 🧭

Now is a good time to talk about the four compass points north, east, south, and west.

In the above quote by Stephen Hawking about the Big Bang, you will notice he uses the word south two times, one of which is capitalized.

As a general rule, we do not capitalize the compass directions.

• The car turned west and disappeared into the sunset.
• Hurricane Katrina started in the Bahamas and moved north, hitting near New Orleans, Louisana.

We capitalize the compass points 1. when they are a part of a name, like the examples below and the one with the South Pole above.

• The official nickname of West Virginia is the Mountain State because, as part of the Appalachian Mountain system, the state is full of hills and mountains.
• Did you know that the South Pole is much colder than the North Pole?

Or 2. when they refer to a specific region or stand for something other than the compass points:

• We do write the West when we talk about the Western part of the world and non-communist countries in Europe.
• We also use capital letters for the Wild West or the Old West to refer to the American Frontier.
• We do write the North and the South when talking about the American Civil War because these are one of the names the warring parties had. We do write the Middle East, Eastern Europe, and the Far East – again, to refer to specific parts (regions) of the world.

A quick note. Such regions may be called differently in different languages. The reasons for this may be geographical or political, or a combination of both.

For example, if we take the Middle East, and translate it with the appropriate term in Bulgarian (близкия(т) изток) or German (Der Nahe Osten), the word middle is substituted with the word near. If we translate that back into English, it would mean the Near East, but it wouldn’t necessarily be the correct term in English.

*Accoring to Encyclopedia Britannica “Middle East and Near East refer to the same region when used today“, even though that hasn’t always been the case.

5. Geographical features and landforms 🏜

We use capital letters for continents, oceans, rivers, lakes, islands, and other geographical formations (mountains, deserts, volcanoes, etc.).

• Europe and Asia are sometimes considered a single continent, Eurasia.
• The Yellow River is also called “China’s Sorrow.”
• How big is the Pacific Ocean?
• The Alps are one of the great mountain ranges in Europe.

Wow 🤯, what a list. Well, there’s even more! To check it out, go to When to (and When Not to) Use Capital Letters in English? Part 2