Because of the Mid-autumn Day happening to _________, we have just enjoyed a longer          National Day vacation than ever before, but it is estimated that it will be 38 years __________       we can experience such a coincidence again.

_____ that there is another good harvest this year.

---You look unhappy, what’s happening, my son? ---I’m wondering how long it’ll be________ we come to China again. 

 For many years we have been keeping in ____by sending each other e-mails or phone calls.

Even on a cold day he prefers ______ out to play football ______at home．