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Chapter 3: Writing Mechanics Help
Chapter 12: Teaching Writing
Chapter 23: Teaching Reading
College English Composition: Help and Review
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Understanding Capitalization Rules

When writing in English, writers must follow certain rules. One important set of rules is the capitalization rules. Capitalizing a letter means to write it as an uppercase (capital) letter. Capitalizing a word means to write the first letter of that word as a capital (uppercase) letter while keeping the rest of the letters in lowercase. For example, to capitalize the word palace, one would write is as Palace.

Why Is Capitalization Important?

Writers and students often wonder about this question: Why is capitalization important?

Capitalization is important for several reasons. First, capitalization rules are part of the grammar and writing rules that writers must adhere to when writing in English. A piece of writing that is written following the proper rules is easier to read and understand. Second, writers capitalize certain words to show their importance or to signal a change in the words’ meanings. Lastly, proper capitalization helps writing to become more effective and clearer.

Proper Capitalization Examples

The following sections detail proper capitalization, while answering this question: What does a writer capitalize?

Proper capitalization rules regarding proper nouns, titles, sentences, pronouns, acronyms, emphasis, and dialogues will be explained.

Proper Nouns

Are all proper nouns capitalized? The answer is yes. While common nouns are nouns that refer to generic persons, places, and things, proper nouns refer to specific persons, places, or things. For example, (a) man is a common noun, but James is a proper noun.

All proper nouns are to be capitalized, meaning the first letter of the proper noun must be written as a capital letter. If the proper noun consists of more than one word, then all the words of the proper noun must be capitalized. For example, Zora Neale Hurston is a proper noun made up of three words; therefore, Z, N, and H are all written as capital letters.

Below is a list showing examples of how to capitalize proper nouns.

Category Examples
Days of the week Saturday, Monday, Friday
Months of the year October, April, May
Holidays Halloween, Juneteenth, Independence Day
Names of people Sara, Latisha, Lloyd Smith
Names of places Apache Boulevard, Eiffel Tower, Caspian Sea
Titles used for people Ms., Mx., Dr.
Names of historical periods or entities Renaissance, Medieval Period, Persian Empire


All the titles of books, magazines, movies, plays, songs, essays, and articles must be capitalized. However, there are certain rules to be followed in this regard.

1.The first word of the title must be capitalized.

2.All the major words must be capitalized.

  • Major words are nouns, verbs, adjectives, adverbs, pronouns, and all words that are four or more letters (including prepositions and conjunctions).

3.All the minor words must be written in lowercase.

  • Minor words are conjunctions, prepositions, and articles.

Examples Explanations
Song of Solomon This is a book title. Song and Solomon are major words; hence, they are capitalized. Of is a short preposition; it is in lower case.
Of Mice and Men This is an example of a movie title. Mice and Men are major words; although they are short, they are capitalized because they are nouns. And is a short conjunction in lowercase. Of is the first word of the title; therefore, it is capitalized.
Mathematical Modeling of the Adaptive Immune Responses in the Early Stage of the HBV Infection This example shows the title of a scientific article. All the words are capitalized except for the prepositions of and in and the article, the.
The Creator Has a Master Plan This example depicts the title of a song. All the words are major words except the article, a. So, all the words are capitalized except for the article, a.

An example of a book title with correct capitalization.

Capitalization rules

First Word in a Sentence

The first word of a sentence must always be capitalized regardless of the word’s length or part of speech. A period at the end of a sentence marks the end of one thought, and the capital letter in the beginning of a new sentence marks the beginning of a new thought. This is why it is important to start a new sentence with a capital letter.

Example Explanations
Arizona is located in the Southwestern part of the United States. It is the sixth largest state and the fourteenth most populous state in the country. Phoenix is its capital city. This state is home to one of the largest universities in the U.S., Arizona State University. This example has four sentences. Each sentence starts with a capitalized word. The capitalized words marking the beginning of each sentence are: Arizona, It, Phoenix, and This.

The Pronoun “I”

The pronoun I is the only pronoun that must be capitalized under any and all circumstances.

Examples Explanations
I graduated from Chandler Community College. I is capitalized; it is the first word of the sentence.
Every month, my daughters and I go on a shopping spree. I is capitalized; it is in the middle of the sentence.


Writers can choose to capitalize one, or a few, words in their writings for emphasis. For example, one might write “Please remember to buy Skim or SKIM milk” to emphasize that the milk must be skim. However, these days, with the ubiquity of texts and emails, writing a whole sentence, or even more than a few words, all in capital letters, might convey the feeling of shouting and rudeness. Although it is possible to show emphasis with a capitalized word, other options such as bolding or highlighting the word, if possible, are more encouraged.


Dialogues in books or plays must also be written according to capitalization rules. The following is an example of a dialogue:

“Please remember to get us some milk,” said Molly.

“Ok. I will not forget,” replied Sally as she was closing the door.

Molly ran to the door and shouted, “Make sure it is skim.”

“I know,” Sally rolled her eyes and said, “skim”.

As shown in the above example, a complete sentence always starts with a capital letter. In dialogues this is regardless of where the sentence is located, in the beginning, middle, or end of the dialogue. For instance, the sentence “Please remember to get us some milk.” is in the beginning of the sentence starting with capital P. However, the sentence “Make sure it is skim.” is at the end of the sentence, but it starts with capital M to mark the beginning of a new piece of dialogue, which is also a complete sentence. If the words in the quotation do not constitute a complete sentence, then no capitalization is necessary. The last line of the above dialogue ends with the word skim in quotations; it is not a sentence, so no capitalization is necessary.


Acronyms are words that are formed from the initials of each major word of a phrase. Every single letter in an acronym must be capitalized.

Acronyms Complete Phrases
OPEC Organization of the Petroleum Exporting Countries
UN United Nations
EU European Union
PIN Personal Identification Number
CIBC Canadian Imperial Bank of Commerce

Tips for Using Capitalization

The table below shows examples of common mistakes that writers make with capitalization. Explanations and tips on how to avoid these mistakes are also provided.

Capitalization Mistakes Explanations and Tips Correct Version
I Know Why The Caged Bird Sings In a book title, only the major words are to be capitalized. I Know Why the Caged Bird Sings
James Baldwin was born in the Summer of 1924, on Saturday August 2nd. While weekdays and months are capitalized, seasons are not. James Baldwin was born in the summer of 1924, on Saturday August 2nd.
these premises are under cctv surveillance. Every sentence must start with a capital letter. In addition, acronyms must be in capital letters. These premises are under CCTV surveillance.
My colleagues and i are happy to host your lecture. The pronoun I must always be capitalized regardless of its location in the sentence. My colleagues and I are happy to host your lecture.
Arizona state university All the words in a proper noun must be capitalized. Arizona State University

An example of capitalized proper nouns: Arizona State University

Capitalization rules

Lesson Summary

Capitalization rules play an important part in making writing effective and clear. It is important to capitalize certain words, so readers can recognize how important the words are and can recognize a possible change in meaning.

Proper nouns, the pronoun I, acronyms, and major words in a title should be capitalized. Also, every sentence must start with a capital letter to mark the beginning of a new thought.

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