--- Whose French book is it?--- It __________ be Lucy’s. Look! Her name is on the book!
You never know how much difficulty we had _________________ the problem. Luckily, we try to solve it with Mrs Wu’s help.
--- How hard-working the teachers are! --- I agree with you. The teachers are always strict __________us.
The film has ___________ for half an hour. Shall we give it up?
The song “trouble is friend” is worth _______________________.
— Why do you look so sleepy in class, John? — Sorry, sir. I __________________ to watch a live Music Festival last night.