根据以下内容回答题：In the United States，it is not customary to telephone someone very early in the morning.If you telephone him early in the day，while he is shaving or having breakfast，the time of the call shows that the matter is very important and requires immediate attention．The same mean-ing is attached to telephone calls made after l l：00 P．m．If someone receives a call during sleeping hours，he assumes it"s a matter of life ot death．The time chosen for the call communi-cares has its importance． In social life，time plays a very important part ineveryday life．In the U．S．A．guests tend to feel they are not highly regarded if the invitation to a dinner party is extended only three or four davs before the party date．But it is not true in all countries．In other areas of the world，it may be considered foolish to make an appointment too far in advance because plans which are made for a date more than a week away tend to be forgotten．The meaning of time differs in dif-ferent Darts of the wodd．Thus，misunderstandings arise between people from cultures that treat time differentlv．Promptness is valued highly in American life．If people are not prompt，they may be regarded as impolite or not fully responsible．In the U．S．no one would think of keep-ing a business associate waiting for an hour，it would be too impolite．A person who is 5 mi-nutes late．he wm say a few words of explaination，though perhaps he will not complete the sentence

“The same meaning is attached to telephone calls made after 11：00 P．m…”Here “attached”means