They will arrive _______ Guangzhou _______ the ninth of July.
The Olympic Games _____ every four years.A. are held B. were held C. are holding
_____Lily_____Lucy may go with you because one of them must stay at home.
Let us forget the past, _____?
---I feel tired and weak.---Why not stop_____.
Yang Liwei_____about twenty-one hours in_____around the earth fourteen times.