There’s too much noise outside. _________ of us two can fall asleep. 

The maths problem is ______ hard for us ______ solve.

My mother likes volleyball. She thinks (认为) it is _______.

—What do you think of Liu Huan?—Oh, he is my favourite singer. I think no one can sing________.

Be ________. Make sure not to make the same spelling mistake next time.