Sunday is more like Monday than it used to be. Places of business that used to keep daytime “business hours” are now open late into the night. And on the Internet, the hour of the day and the day of the week have become irrelevant. A half century ago in the United states, most people experienced strong and precise dividing lines between days of rest and days of work, school time and summer time. Today the dividing lines are still there, but they seem not clear.
The law in almost all states used to require stores to close on Sunday; in most, it no longer does. It used to keep the schools open in all seasons except summer, in most, it still does. And whether the work week should strengthen its legal（法律的）limits, or whether it should become more changeable, is often debated（争论）. How should we, as a society, organize our time? Should we go even further in relaxing the dividing lines of time until we live in a world in which every minute is much like every other?
These are not easy questions even to ask. Part of the difficulty is that we seldom recognize the “law of time” even when we meet it face to face. We know as children that we have to go to  school a certain number of hours, a certain number of days, a certain number of years – but unless we meet the truant officer（学监）, we may well think that we should go to school because of social custom and parents’ requirement rather than to the law. As adults we know “extra pay for overtime working” very well, but less familiar with the fact that what constitutes（构成）“overtime” is a matter of legal thing. When we turn the clock forward to start daylight – saving time, have we ever thought to ourselves: “Here is the law in action”? As we shall see, there is a lot of law that has great influence on how organize and use time: compulsory education law, overtime law, and daylight-saving law – as well as law about Sunday closing, holidays, being late to work, time zones, and so on. Once we begin to look for it, we will have no trouble finding a law of time to examine and assess.
What does the underlined word “irrelevant” probably mean?

A．Impossible.

B．Unacceptable.

C．Unimportant.

D．Disagreeable.

The writer raises the questions in Paragraph 2 to introduce the fact that people _____.

A．are unknowing of the law of time

B．fail to make full use of their time

C．welcome changeable working hours

D．enjoy working overtime for more pay

We can learn from the passage that most children go to school because they_____.

A．have to follow the law

B．need to find social customs

C．need to learn more knowledge

D．have to follow their parents’ requirement

What is the main idea of the passage?

A．Our life is governed by the law of time.

B．How to use time is not worth debating.

C．New ways of using time change our society.

D．Our time table is decided by social customs.