Choose the correct item

1. He fixed the car all by
   [himself|itself|yourself].
2. If Michael
   [buys|bought|is buying] a new computer, he will let us use it.
3. When babies are happy, they
   [would smile|smile|are smiling].
4. [If|Unless|Must] you go to bed early, you will be tired in the morning.
5. I burnt
   [myself|itself|himself] while I was cooking supper.
6. I go to sleep
   [unless|when|so] I'm tired.
7. They entertained
   [themselves|ourselves|yourselves] for hours by playing a game.
8. I won't do it
   [if|when|unless] you ask me nicely. You must learn to be polite.
9. If you exercise regularly, you
   [will|won't|can] have more energy.
10. She finished the exercise by
    [ourselves|himself|herself]. Nobody helped her.