They _____have arrived at lunchtime but their flight was delayed. [ ]

Every one of us must know this: _________ we live can we save the earth．

_____ the website of the Fire Department in your city, and you will learn a lot about firefighting

Did you get home a little earlier yesterday—No It was six o’clock________ we got home

no one ____ me, for I can deal with it all bymyself