阅读下列短文，从每题所给的A,B,C和D项中,选出最佳选项并在答题卡上将该项涂黑。
A
In the United States, friendships can be close, constant, intense, generous and real, yet fade （暗淡下来）away in a short time if circumstances change. Neither side feels hurt by this. Both may exchange Christmas greetings for a year or two, perhaps a few letters for a while—then no more. If the same two people meet again by chance, even years later, they pick up the friendship where it left off and are delighted.
In the States, you can feel free to visit people’s homes, share their holidays, enjoy their lives without fear that you are taking on a lasting obligation（负担）. Do not hesitate to accept hospitality （热情款待）because you can’t give it in return. No one will expect you to do so for they know you are far from home. Americans will enjoy
