Help Alex interview a potential new roommate by choosing the correct question word for each gap in his notes.

"So, when do you usually wake up on weekends?"

"Out of curiosity, how often do you clean the apartment?"

"By the way, who is your favorite person to invite over?"

"So, when do you usually wake up on weekends?"

Use "when" to ask about time.

"Out of curiosity, how often do you clean the apartment?"

Use "how often" to ask about frequency or habits.

"By the way, who is your favorite person to invite over?"

Use "who" to ask about a person.