Verified answer

1. Someone phoned you today, but he didn't tell me his name.

2. Everybody was having lunch in the restaurant, so there was no one in the office.

3. Are you worried about something? - No, nothing is worrying me.

4. What did you buy at the shops? - I bought nothing. I couldn't find anything I liked.

5. That's a very easy job. Everyone can do it.

1 - someone

2 - nobody

3 - nothing

4 - something, anything

5 - everyone