There’s talk today about how as a society we’ve become separated by colors, income, city vs suburb, red state vs blue．But we also divide ourselves with unseen dotted lines．I’m talking about the property lines that isolate us from the people we are physically closest to: our neighbors．
It was a disaster on my street, in a middle-class suburb of Rochester Town, several years ago that got me thinking about this．One night, a neighbor shot and killed his wife and then himself; their two middle-school children ran screaming into the night．Though the couple had lived on our street for seven years, my wife and I hardly knew them．We’d see them jogging together．Sometimes our children would share cars to school with theirs．
Some of the neighbors attended the funeral（葬礼）and called on relatives．Someone laid a single bunch of yellow flowers at the family’s front door, but nothing else was done to mark the loss．Within weeks, the children had moved with their grandparents to another part of the town．The only indication that anything had changed was the “For Sale” sign in front of their house．
A family had disappeared, yet the impact on our neighborhood was slight．How could that be? Did I live in a community or just in a house on a street surrounded by people whose lives were entirely separate? Few of my neighbors, I later learned, knew others on the street more than casually; many didn’t know even the names of those a few doors down．
Why is it that in an age of low long-distance expenses, discount airlines and the Internet, when we can create community anywhere, we often don’t know the people who live next door? Maybe my neighbors didn’t mind living this way, but I did．I wanted to get to know the people whose houses I passed each day – not just what they do for a living and how many children they have, but the depth of their experience and what kind of people they are．
What would it take, I wondered, to break through the barriers between us? I thought about childhood sleepovers（在外过夜）, and the familiar feeling and deep understanding I used to get from waking up inside a friend’s home．Would my neighbors let me sleep over and write about their lives from inside their own houses?
72．The underlined word “this” in the second paragraph probably refers to the talk about ____．
A．how a society is divided by dotted lines 
B．the property lines separating us from our neighbors
C．the couple’s death                  
D．understanding each other between neighbors
73．Which of the following is NOT TRUE according to the author’s description?
A．The husband killed himself．
B．The couple had the habit of jogging together．
C．Their children moved to live with grandparents after the couple’s death．
D．The author never knew the couple until they died seven years later．
74．From the last paragraph, we can infer that the author _____ in his childhood．
A．had once slept in the open air outside
B．had slept in his friend’s home more than once
C．had slept at home but woke up to find himself inside his friend’s home
D．used to live in his friend’s home
75．Following the last paragraph, the author will perhaps _____．
A．leave his home and began his writing career
B．sleep in the open air and write about his experiences
C．sleep in his neighbors’ homes and write about their family lives
D．interview his neighbors and write about their houses