—What does the sign over there read?—"No person_______ smoke or carry a lighted cigarette, cigar or pipe in this area．"

We ________ jump to conclusions before we have all the facts.

He is not native, if he were, we _______ this discussion over his identity.

He ______ the key, so we ______ into the office.

The professor ________at 8 o’clock，but he has not shown up yet，which worries all of us.