Mary is _____ girl.
--- Excuse me, when and where will the next Olympic Games take place?--- The 31st Olympic Games _______ in Rio de Janeiro, the capital of Brazil in 2016.
---Look! Such heavy traffic!--- I doubt _________ or not I can get to school on time.
--- Our school is so beautiful.--- Yes. So our teachers ______ at school to enjoy its beauty.
--- What do you think of the students of Meiling Middle School?---They study _____ harder than before.[]
No matter what happens, the fact that Diaoyu Island belongs to China will ______ change.