"Mary, turn off the water_________you are brushing your teeth. " "Sorry, I'll do it at once. "A. until B. while C. during
--- What are you talking about? --- We are discussing ________.
--- Do you know which room Tom lives? - No. I don’t know the room______.
--- Help yourself to some more soup. --- .
--- Would you like me to help you? --- .
--- Where’s Bob? --- He_____ to the library.