If human beings had been a bit less greedy and cruel, more birds and animals ______ dying out. [ ]

I can’t tell when that house ______ exactly, but it must be very long ago.

April29,2011____Prince William and Kate Middleton walked into the palace hall of thewedding ceremony.

Let’s climb the mountain.—I don’t agree. _______ the mountain will make us exhausted.

Must I turn off the gas after cooking—Of course. You ________ never be careful enough with that.