1) He has travelled around the USA.
" - " He hasn't travelled around the USA.
" ? " Has he travelled around the USA?
2) The have come home.
" - " They haven't come home.
" ? " Have they come home?
3) My parents have booked me a week at a cool camp.
" - " My parents haven't booked me a book at a cool camp.
" ? " Have my parents booked me a week at a cool camp?
4) I have made other plans.
" - " I haven't made other plans.
" ? " Have I made other plans?