--- Is Lucy knocking at the door?--- No. It ______ be Lucy. She is in America now.
John had a short walk after lunch,_______?
---How often do you see your grandparents? ---_______.
_______ fine day it is! Let’s go and fly a kite.
---Which city has _______ population, Shanghai, Hongkong, or Qingdao? ---Shanghai, of course..
Just like weather, life_______ be sunny and beautiful all the time.