Read the following dialogue then answer the questions!

Mr. Dhomah: Good morning, students. How are you today?

Students: Good morning, sir. We are fine. Thanks. And you?

Mr. Dhomah: I'm very well, thanks. Are you okay, Tara? Why did you not answer my greeting?

Tara: I am sorry, Sir. I'm dizzy. I have a headache.

Mr. Dhomah: Oh, I see. If you are sick, you may have a rest at the school clinic.

Tara: May I, Sir?

Mr. Dhomah: Yes, of course.

Tara: Thank you, Sir.

Mr. Dhomah: You're welcome.

“I'm sorry, Sir.” The bold words are to express . . . .