1. They _______ (chat) online when Amy came up the stairs.
2. When I got home, I found my pet dog _______ (lie) on the floor, dead.
3. —I'm sorry I forgot _______ (post) your letter on my way home. 
    —That's OK. I will do it myself this afternoon.
4. She tells her son to have his hair _______ (cut) every other month.
5. Yesterday, she ________ (make) to finish all the work in a short time by his boss.