Everyone knows that _______ is dangerous to play with fire, but _______ is difficult is to prevent children from playing with fire.

---Tom, supper is ready.----I don't want to eat____________ ,Mum. I'm not feeling well.

He wanted to read more,so he asked his friend if there was      to read.

I think _________ can make Andy change his mind. He is such a person who never gives up easily.

Some people would rather ride bicycles as bicycle riding has _____ of the trouble of taking buses.