I’d love to come to your beautiful house.If you invite me, I _______ say “no”.

Most people find it hard to ________Beijing Opera to foreigners because of cultural differences.

the time of great trouble, thesoldiers _______ their spirits by singing

I intend to buy a present for my mother’s birthday, ________ at the proper price but of great value.

Peter, can you tell me the differences _____ the four words—- Sorry, I don’t know.