One night Mrs. Riley, an elderly woman, was walking along a dark prefix = st1 /Londonstreet. She was carrying her handbag in one hand and a plastic carrier bag in the other. There was nobody else in the street except two young men. They were standing in a dark shop doorway. One of them was very tall with fair hair, the other was short and fat with a beard. The two young men waited for a few moments, and then ran quickly and quietly towards Mrs. Riley. The tall one held her from behind while the other one tried to seize her handbag. Suddenly Mrs. Riley threw the tall one over her shoulder. He crashed into the other one and they both landed on the ground. Without speaking, Mrs. Riley struck both of them on the head with her handbag and walked calmly away. The two surprised young men were still sitting on the ground when Mrs. Riley crossed the street towards a door with a lighted sign above it. Mrs. Riley paused, turned round, smiled at them and walked into the South West London Judo   Club. The two young men were standing in a dark shop doorway because_.
they had nothing to do they were homeless they were waiting for a victim they were guarding the shop