Ответ:

  1. Is there anybody in the classroom?
  2. Somebody is at the door. I’ll open it.
  3. I don’t know where Jane is. She is somewhere on holiday.
  4. Is there anything in your bag?
  5. Were you anywhere last summer?
  6. I’ve got something in my bag. Guess what it is.
  7. Did you meet anybody in the park?

Перевод: something/somebody/somewhere употребляются главным образом в утвердительных предложениях, anything/anybody/anywhere — в вопросах и отрицаниях.