Respuesta:
1. I know how to knit, so I make a lot of scarves and sweaters myself.
2. My little sister decorated the house for the Halloween party by herself.
3. Samantha did the science project because her partner got sick.
4. Bob lives alone, so he cooks and does the laundry by himself.
5. My dog is very intelligent. It can open the front door by itself.
6. Janice cut herself with a knife.
7. Why is your dog scratching itself all the time?
8. Did you and Mary enjoy yourselves at the party last night?
9. Mr. Smith, the new math teacher, introduced himself to the class yesterday.
10. I didn't find a mechanic, so I fixed my motorcycle myself.