23. Often he _________ sit for hours doing nothing at all when he was in low spirits.

22. Eric _________ go camping with us this Sunday, but he isn’t quite sure yet.

35. The plant is dead. I ______it more water.

29. If you ______ go, at least wait until the rain stops.

26. —Who______ it be that is knocking at the door?  
—It ______ be Father, but I’m not sure.

25. – _____ we take a rest? I can’t go any further.
– You _____ be tired — we’ve only walked for 20 minutes!

8．Without your kind help, we ______ in the experiment.

7．Since you are here, you ____ as well stay here for long.

28．You___________use your cell phone here in our hospital because of the disturbance to the electronic equipments! It’s forbidden．

28. What was unexpected was that the disrespectable fellow ______ the old man.