+=my sister eats poridge every day.
- =my sister doesn't eat poridge every day.
?=does my sister eat poridge every day?
+=we bought sweets.
- =we didnt buy sweets.
?=have we bought sweets?
+=my friends are dancing now.
- =my friends aren't dancing now.
?=are my friends dancing now?
+=my parents have read this book.
- =my parents haven't read this book.
?= have my parents read this book?