The old man lives alone on an island, and his home is not accessible ______ by boat.
— Let’s Football World tonight, Frank. Okay? Just this once! — Let me guess. You want to watch the History Channel, don’t you?
—Shall Tom go and play football? —Not unless he ______ his homework.
There is no doubt that the official was very weak-willed, otherwise he .
Helen didn’t mention anything about the dinner over the phone; she seemed about our appointment.
Many people see the computer as a “magic box”, and are not concerned with ______ it works.