It was at a concert that I happened to find David.He was holding his head at a strange __  (1)  __as if he were staring down at something.Then the truth struck me.He was blind.The last thing he remembers __  (2)  __was his daughter being born.Then the world went __  (3)  __.

Bad luck is no stranger to this 44-year-old man.His mother died of cancer，and his weak father had to __  (4)  __11-year-old David to the care of the state.

Things seemed always to go from bad to __  (5)  __.Two years ago，his beloved guide dog pulled him out of the __  (6)  __of a truck.David was not hurt.The dog __  (7)  __.

But David does not feel sorry for himself.“These are just little obstacles (障碍)you have to __  (8)  __in your life，”he said.

He has to make a daily two-hour trip to his working place—the X-ray department of an__  (9)  __ room.

It was a hard job to __  (10)  __.Before he got it，David was determined to escape the workshop run by the Lighthouse，an organization __  (11)  __ to help blind people.He wanted a job of developing X-ray film，something __  (12)  __，not just he，must do in the dark，including people with __  (13)  __eyesight.The Lighthouse called many hospitals，with no result，__  (14)  __they offered to pay his first three monthsˈ salary.

David works alone in a dark room that __  (15)  __ of chemicals.He cannot wear gloves.__  (16)  __，he could not feel.Since this is an emergency room，lives can be put __  (17)  __or out of danger.His directress says she trusts him 100 percent.

He makes $ 20,000 a year.But his motivation(动机)goes __  (18)  __money.“By working，I can actualize my own __  (19)  __.Thatˈs the most important！”he said.

What a shining example for us to __  (20)  __！