Preposition - "By"

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 - "At"

Preposition – “At”

The preposition at can be used to indicate a specific moment or point in time. Here are some examples: The meeting is scheduled at 3:00 PM. I'll be ready to leave at 8:30 in the morning.