sentence: I used to spend my whole holidays at my grandparents ' country house , surrounded by green fields , forest and rivers , but when I turned eighteen my mother thought I was old enough to take a plane on my own and stay with her for a month .
modified: I used to spend my whole holidays at my grandparents ' country house , surrounded by green fields , forest and rivers , but when I turned eighteen my mother thought I was old enough to take a plane on my own and stay with her for a month .
transformation: noop