A report brought back by most visitors to the US is how friendly, polite, and helpful most Americans were to them. To be fair, this observation is also frequently made of Canada and Canadians, and should best be considered North American. There are, of course, exceptions. Small-minded officials, rude waiters, and ill-mannered taxi drivers are hardly unknown in the US. Yet American’s friendliness and helpfulness is an observation made so frequently that it deserves comment.
For a long period of time and in many parts of the country, a traveler was a welcome break in an otherwise dull existence. Dullness and loneliness were common problems of the families who generally lived distant from one another. Strangers and travelers were welcome sources of distraction, and brought news of the outside world．
The tough realities of the border also shaped this tradition of hospitality. Someone traveling alone, if hungry, injured, or ill, often had nowhere to turn except to the nearest settler agent. It was not a matter of choice for the traveler or only a charitable impulse (冲动） on the part of the settlers. It reflected the hardship of daily life: if you didn't take in the stranger and take care of him, there was no one else who would. And someday, remember, you might be in the same situation．
Today there are many charitable organizations which specialize in helping the exhausted traveler. Yet, the old tradition of hospitality to strangers is still very strong in the US, especially in the smaller cities and towns away from the busy tourist routes. "I was just traveling through, got talking with this American, and pretty soon he invited me home for dinner, amazing." Such observations reported by visitors to the US are not uncommon, but are not always understood properly. The casual friendliness of many Americans should be understood neither as superficial（表面的）nor as artificial（虚伪的）, but as the result of a historically developed cultural tradition.
As is true of any developed society, in America a complex set of cultural signals and customs is the basis of all social inter-relationships. And, of course, speaking a language does not necessarily mean that someone understands social and cultural patterns. Visitors who fail to "translate" cultural meanings properly often draw wrong conclusions. For example when an American uses the word "friend", the cultural meanings of the word may be quite different from those it has in the visitor's language and culture. It takes more than a brief encounter on a bus to tell polite customs from individual interest. Yet, being friendly is a virtue （美德） that many Americans value highly and expect from both neighbors and strangers.
In the eyes of visitors from the outside world, ________．

A．rude taxi drivers are hardly seen in the US

B．small-minded officials deserve a serious comment

C．Canadians are not so friendly as their neighbors

D．most Americans are ready to offer help

We can know from the last paragraph that _______．

A．culture has an influence over social inter-relationship

B．polite customs and individual interest are inter-related

C．various virtues shows themselves only among friends

D．social inter-relationships equal the complex set of cultural customs

Families who lived far from one another used to entertain strangers _______．

A．to improve their hard life	B．in view of their long-distance travel
C．to add some taste to their own daily life	D．out of a charitable impulse

The tradition of hospitality to strangers _______．

A．tends to be superficial and artificial

B．is generally well kept up in the United States

C．is always understood properly

D．has something to do with the busy tourist route