. The police refused to _____ the clues they were working on.
These new measures will put many small businesses at __________ risk, so he must look for __________ way out.
Once upon a time, a (n)__________ famous scientist said that life was not easy for any of us but first of all we should believe in ourselves.
He let me repeat his instructions __________ sure that I understood what was __________ after he went away.
David couldn't tell __________ from far away whether the green traffic light meant going straight or turning left.
-Are you a volunteer now? -No, but I __________. I worked for the City Sports Meeting last year.