rks, ________ of gun powder or flashpowder _______ in a tight paper tube, make the big flash or boom effect.

We students must these school rules. They are good for us.

They live 20 kilometres _________ the school.

It’s hard for me to go to sleep. —Try to ______the amount of coffee you drink during the day.

Mary has caught a bad cold.—Has she? I regret _____ her to put on more clothes yesterday.