单项选择题

We may look at the world around us, but somehow we manage not to see it until whatever we’ve become used to suddenly disappears. (36) , for example, the neatly-dressed woman I (37) to see-or look at-on my way to work each morning.
For three years, no matter (38) the weather was like, she was always waiting at the bus stop around 8:00 am. On (39) days, she wore heavy clothes and a pair of woolen gloves. Summertime (40) out neat, belted cotton dresses and a hat pulled low over her sunglasses. (41) , she was an ordinary working woman. Of course, I (42) all this only after she was seen no more. It was then that I realized how (43) I expected to see her each morning. You might say I (44) her.
"Did she have an accident Something (45) " I thought to myself about her (46) . Now that she was gone, I felt I had (47) her. I began to realize that part of our (48) life probably includes such chance meetings with familiar (49) : the milkman you see at dawn, the woman who (50) walks her dog along the street every morning, the twin brothers you see at the library. Such people are (51) markers in our lives. They add weight to our (52) of place and belonging.
Think about it. (53) , while walking to work, we mark where we are by (54) a certain building, why should we not mark where we are when we pass a familiar, though (55) , person