I have never seen any unidentified flying objects.
Have you ever been in Japan?
I haven't written my homework.
He hasn't bought anything for my birthday.
They have lived in that ugly flat for 5 years.
I haven't met my neighbor from my home town since I was 10 y.o.
She hasn't read any English book.
We haven't tried to climb that high pick.
Have you ever cooked such a tasty food?
They have cleaned their rooms.
