How to use Who in sentences

 "Who" is a versatile pronoun used to refer to people. It's primarily used in three ways: as an interrogative pronoun (to ask a question), as a relative pronoun (to connect clauses), and in a less common, indefinite sense.

1. As an Interrogative Pronoun (To ask a question)

This is the most common use of "who." It is used to ask about a person or people.

• To ask about a person's identity:

  • Who is at the door?

  • Who are you?

• To ask about the person performing an action (the subject of a verb):

  • Who broke the window?

  • Who is going to the party?

• To ask about the person receiving the action (the object of a verb or preposition):

  • Who did you see at the store? (Grammatically, "whom" is more correct here, but "who" is very common in spoken and informal English.)

  • To whom did you give the book? (Using "whom" after a preposition is the formal rule.)

2. As a Relative Pronoun (To connect clauses)

"Who" is used to introduce a relative clause, which adds more information about a person (or people) mentioned in the main clause. It functions as the subject of the relative clause.

• To refer to a person who is the subject of the relative clause:

  • The man who lives next door is a doctor. (The relative clause "who lives next door" describes "the man.")

  • She is the student who won the prize. (The relative clause "who won the prize" describes "the student.")

• To refer to a person who is the object of the relative clause:

  • The person who I met yesterday was very friendly. (Again, "whom" is technically more correct, but "who" is widely used.)

  • He is the friend who I invited.

3. In Fixed Phrases

"Who" is also a key part of several common phrases.

• Who knows?: An expression of uncertainty.

  • "Will it rain tomorrow?" - "Who knows?"

• Who cares?: An expression of indifference.

  • "He didn't invite me." - "Who cares? We can still have fun."

• As for who...: Used to introduce a person or group in a new part of the sentence.

  • He gave gifts to everyone. As for who got what, I don't know.

Key Distinction: "Who" vs. "Whom"

• Who is a subject pronoun (like "he" or "she"). It is used when the person is the one performing the action.

  • Who is coming? (They are coming.)

• Whom is an object pronoun (like "him" or "her"). It is used when the person is the one receiving the action.

  • Whom did you call? (I called him.)

While "whom" is grammatically correct, it is often considered formal or old-fashioned. In most everyday conversation and writing, "who" is used for both subject and object roles, though it's good to be aware of the distinction for formal writing.