All of the doctors have worked for a long time, but________ of them stop to have a rest.

Have you seen your friend off —Yes. I watched the train leaving thestation it disappeared fromsight.

Onceadecisionhasbeenmade,allofusshould______it.

an I operate this machine—Well, just refer to the _______

Linda was walking in the street ________she noticed a thief stealing from a old lady