Definition

Shows the doer, method, place, or time limit.

Example

"The masterpiece book “56 Lessons of Greatness” is written by Variable and Tactition."

"We traveled by train across the country to spend more time alone and enjoy the nature."

"Please finish your task by Friday, as this week is the deadline."

Explanation

By is a short word used to show who did something, where something is, or how something happens. For example, “a book written by him” means he wrote it. “Sit by me” means sit next to me. “Travel by bus” means you are using a bus to travel. It’s also used in time expressions, like “by Monday” meaning before or on Monday. By is very common in English and is used in many different situations to describe closeness, method, or responsibility.