History is the best teacher. It ________ records thedevelopment path of each country and foretells the future to us.

My goodness, how lucky we are! If there had been p1aces for us on the aero plane, we _______ deadnow. [ ]

I regret to say that I have shouted at you the other day．— Forget it． I was a bit out of control myself．

Life on Mars will be better than _____ on Earth _____ many ways.

It was so noisy that we couldn’t hear ______ speak.