Tag: as an adverb
Preposition – “By”
Preposition by as an agent or doer: In passive voice constructions, the preposition by is often used to indicate the doer or agent of the action. Here are some examples: The book was written by Mark Twain. In this sentence, by indicates that Mark Twain is the person who wrote the book.
Preposition – “About”
In these examples, about is used to convey an approximate or estimated value or quantity, indicating that it's not exact but close to the stated amount of time.