The CDs are on sale！Buy one and you get ______ completely free.

---I heard that Bill was scolded by the teacher last week. ---Ah, yes. The teacher wanted to check his exercises, but ___ was finished at all.

Of all my friends,__________ is so diligent as Tom.

He is a strict but kind teacher, ＿＿my son loves and respects.

Sonny is often late for school, and      makes her teacher very angry.