I moved to a new neighborhood two months ago. In the house with a large 1 across the road lived a taxi driver, a single parent with two school-aged children. At the end of the day, he would2 his taxi on the road. I3 why he did not park it in the garage.

    Then one day I learnt that he had another car in his garage. In the afternoon he would come home 4work, leave his taxi and go out for his 5 affairs in his other car, not in his taxi. I felt it was6.

    I was curious to see his personal car but did not make it until I 7 to be outside one evening two weeks later, when the garage door was8 and he drove out in his “own” car: a Rolls-Royce（劳斯莱斯）! It shook me completely 9 I realized what that meant. You see, he was a taxi driver. But deep inside, he saw himself as something else: a Rolls-Royce owner and a（n）10 . He drove others in his taxi but himself and his children in his Rolls-Royce. For him, a taxi was just something he drove for a living. Rolls-Royce was something he drove for a (n）11.

    We go to bed every night and 12 every morning as parents or children, not as bankers, CEOs or professors. We go for a party as close friends or go for a vacation as a 13. We love life as it is. Yet often, we base our entire happiness and success on how high we 14 the social ladder（梯子）And we never use our Rolls-Royce, by keeping it dusty in our garage. We should focus more on 15we are than what we do!

如图，在△ABC中，AC=2，∠A=45°，tanB= $\frac{1}{2}$ ，求BC的长