Something ___ to save our earth. Do you think so?
He felt he wasn’t worth _______ such a great honor.
The whole family still live in the house, most of _____ windows face south.
Henry, take this seat, ________ you’ll have to stand watching the game.
_____ mobile phone is very convenient, school children are not allowed to own one.
Lucy didn’t do well in this exam, ______ made her mother quite unhappy.