26. The old woman could not _____ the terrible noise, and she had to close the door and windows.

27. When he heard the news, his heart ______ very fast.

28. They ____ friends since they met in Shanghai ten years ago.

29. That's all for the party. Let's _____.

30. The coal we use today should _____ plants and trees.

31. Do you know when did the world _____?

32. I ____ what he said, but I don’t _____ him.

33. --- Do you think it’s to rain over the weekend?

--- _____.

34. ----There's something wrong with the machine. Who is _____?

-----None. The machine is too old to work.

35. The poor old man _____ blind when he was very young.