Someone you work with has come over to your house to visit. You offered him something to drink, and he said that he'd like a coffee. You ask him this to find out if he likes sugar and milk in it.
A coworker is visiting you at your home for the first time. You want to be polite, so you offer him something to drink.
Your nephew is visiting your house. He seems to be cold. You offer to turn the heat up.
You're at your uncle's house. It's pretty cold. You'd like your uncle to turn the heat up, and you also want to know why it's so cold there. You ask him this question.
You're talking to your friend about a book that you recently read. It was a really good book, so you stayed up late every night reading. You say this to your friend to explain why.