Letter Case Rules

Using uppercase and lowercase letters correctly is essential for clear, professional, and grammatically correct writing in English. Let's explore the rules that govern when and how to use them.

When to Use Uppercase

Capital letters signal importance and mark beginnings.

  • First Word of a Sentence

    e.g., She is reading a book.

  • Proper Nouns

    e.g., My friend, Priya, lives in India.

  • The Pronoun "I"

    e.g., He asked if I was ready to go.

  • Days, Months, and Holidays

    e.g., We have a meeting on Monday in January.

  • Titles of People (with names)

    e.g., We spoke to Doctor Smith.

  • Main Words in Titles

    e.g., My favorite book is "A Tale of Two Cities".

  • Languages & Nationalities

    e.g., He speaks English and is American.

When to Use Lowercase

Most words in a sentence are in lowercase.

General Words

Use lowercase for most words in the middle of a sentence unless they are proper nouns.

Common Nouns

Words like 'book', 'car', or 'river' are not capitalized unless they are part of a specific name (e.g., the Amazon River).

Small Words in Titles

Short prepositions, conjunctions, and articles (like 'of', 'in', 'and', 'the') are not capitalized in titles unless they are the first or last word.

Quick Summary: Uppercase vs. Lowercase

Use CaseCapitalize?
First word of a sentenceYes
Proper nouns (e.g., John, London)Yes
Common nouns (e.g., boy, city)No (unless at start of sentence)
The pronoun "I"Yes
Days, months, holidaysYes
Seasons (e.g., summer, winter)No

Practice Your Skills

Ready to test your knowledge? Try these exercises and worksheets.