When to use IN ON or BY? English Prepositions Lesson & Quiz | Grammar Made Easy | Definition and Examples

Learn how to use the English prepositions IN, ON, and BY with clear examples and easy explanations. Perfect for improving your grammar.

Understanding when to use IN, ON, and BY can be tricky, but mastering these prepositions is essential for clear communication in English. In this guide, we'll break down how to use these prepositions with easy-to-understand examples.

1. When to Use IN

IN is used in various contexts, particularly with time, place, and abstract ideas:

• Time:

  • Months: "We’ll meet in July."
  • Years: "She was born in 1990."
  • Seasons: "The leaves change color in autumn."
  • Long Periods: "He was a student in the 1980s."

• Place:

  • Inside Something: "The cat is in the box." / "She lives in New York."
  • General Areas: "They are in the park."

• Abstract Ideas:

  • Feelings or States: "She is in a good mood." / "They are in trouble."

2. When to Use ON

ON is typically used for specific days, dates, surfaces, and certain locations:

• Time:

  • Specific Days: "Let’s meet on Friday."
  • Dates: "Her birthday is on December 25th."

• Place:

  • Surfaces: "The phone is on the table." / "There’s a picture on the wall."
  • Streets or Public Transport: "He lives on Main Street." / "They’re on the bus."

3. When to Use BY

BY is often used to indicate deadlines, proximity, or methods:

• Time:

  • Deadlines: "Finish your homework by tomorrow." / "I need to be home by 6 PM."

• Place:

  • Near or Next To: "The store is by the park." / "She sat by the fire."

• Means or Method:

  • How Something is Done: "We traveled by car." / "He sent the message by email."

Practice Makes Perfect

To help you master these prepositions, here are some practice sentences:

Fill in the blanks:

• "She was born ____ 2005." 
• "The keys are ____ the table." 
• "Please arrive ____ 4 PM."
• "I left my bag ____ the car."
• "The cafe is ____ the corner." 
• "My birthday is ____ October 15th." 

Choose the right preposition:

• "We’re going to the beach ____ summer."

  • a) in
  • b) on
  • c) by

• "The cat jumped ____ the bed."

  • a) in
  • b) on
  • c) by

• "The package will arrive ____ Monday."

  • a) in
  • b) on
  • c) by

• "She finished the book ____ last night."

  • a) in
  • b) on
  • c) by

Answers:

1. Fill in the blanks:

• "She was born in 2005."
• "The keys are on the table."
• "Please arrive by 4 PM."
• "I left my bag in the car."
• "The cafe is by the corner."
• "My birthday is on October 15th."

2. Choose the right preposition:

• "We’re going to the beach in summer."
• "The cat jumped on the bed."
• "The package will arrive by Monday."
• "She finished the book by last night."

Preposition	Usage	Examples
IN	Time: Months, years, seasons, long periods	- "We’ll meet in July." - "She was born in 1990." - "The flowers bloom in spring." - "He graduated in the 1980s."
	Place: Inside something, general areas	- "The cat is in the box." - "She lives in New York." - "They are in the park."
	Abstract Ideas: Feelings or states	- "She is in a good mood." - "They are in trouble."
ON	Time: Specific days, dates	- "Let’s meet on Friday." - "Her birthday is on December 25th."
	Place: Surfaces, streets, public transport	- "The phone is on the table." - "There’s a picture on the wall." - "He lives on Main Street." - "They’re on the bus."
BY	Time: Deadlines	- "Finish your homework by tomorrow." - "I need to be home by 6 PM."
	Place: Near or next to something	- "The store is by the park." - "She sat by the fire."
	Means or Method: How something is done	- "We traveled by car." - "He sent the message by email."

Mastering the use of IN, ON, and BY can greatly enhance your English skills. By understanding the differences and practicing with these examples, you’ll improve your ability to communicate clearly and effectively. Keep practicing, and soon, using these prepositions will become second nature! 

More Spoken English Topics 

Difference Between "Because" and "Because of"

Affect vs. Effect: What's the Difference?