The passengers watched sympathetically as the woman made her way carefully up the steps. She paid the bus driver and felt the seat（21）was empty. Then she（22）. It had been a year since Susan,34, became blind.Due to a medical misdiagnosis（错误的诊断），she was （23） thrown into a world of darkness, frustration and self-pity. And all that she had to cling （24）was her husband, Mark. Mark was an air-force officer and he loved Susan with all his heart. He was （25）to help his wife gain strength and confidence.For the first two weeks, Mark（26）Susan to and from work each day. He taught her how to rely on her other（27）, especially her hearing, to determine where she was and how to（28）to the new environment. （29）, Susan decided that she was ready to try the trip on her own. （30） Monday morning, she said goodbye, and for the first time, they went their （31） ways. On Friday morning, Susan took the bus to work （32）。 As she was（33）the bus,driver said, the driver said,”Hey, I do （34）you.” Susan didn’t know （35）the driver was talking about, and asked, “What do you mean?” The driver answered.“You know,every morning for the（36）week, a fine-looking gentleman in a military uniform stands across the corner, （37） you get off the bus and cross the street safely. He watches （38） you enter your office building. You are one lucky lady. Tears of （39） poured down Susan’s cheeks. Mark had given her a gift more powerful than sight, a gift that can bring （40）where there is darkness.