Most people feel lonely sometimes, but it usually lasts only a few minutes or a few hours．This kind of loneliness is not serious．In fact, it is quite normal．For some people, though, loneliness can last for years．Now researchers say there are three different kinds of loneliness．
The first kind of loneliness is temporary．This is the most common type．It usually disappears quickly and does not need any special attention．
The second kind, situational loneliness, is a natural result of a certain situation, for example, a family problem, the death of a loved one, or moving to a new place．Although this kind of loneliness can cause physical problems, such as headaches and sleeplessness, it usually does not last for more than a year．
The third kind of loneliness is the most severe．Unlike the second type, chronic （长期的） loneliness usually lasts more than two years and has no specific cause．People who experience habitual loneliness have problems socializing and being close to others．Unfortunately, many chronically lonely people think there is little or nothing they can do to improve their condition．
Psychologists agree that one important factor in loneliness is a person's social contacts, such as friends, family members, co-workers, etc．We depend on various people for different reasons．For instance, our families give us emotional support, our parents and teachers give us guidance, and our friends share interests and activities．However, psychologists have found that, though lonely people have many social contacts, they sometimes feel they should have more．They question then" own popularity．
Psychologists are trying to find ways to help habitually lonely people for two reasons: they are unhappy and unable to socialize and there is a connection between chronic loneliness and serious illness such as heart disease．While temporary and situational loneliness can be a normal and healthy part of life, chronic loneliness can be a very sad and sometimes dangerous condition．
Which of the following can be the cause of situational loneliness?

A．Sleeplessness．	B．Changing work．
C．Heart disease．	D．Social contacts．

The underlined word "it" in the last sentence of the third paragraph refers to _____ ．

A．headaches	B．situational loneliness
C．sleeplessness	D．temporary loneliness

How would you treat temporary loneliness according to the passage?

A．Just ignore it．	B．Talk to friends．
C．Go to see a doctor．	D．Ask your teachers for guidance．

What can we learn from the passage?

A．People feel lonely in a certain situation．

B．There are only three types of loneliness in our life．

C．Loneliness doesn't affect people much．

D．Scientists have found ways to help habitually lonely people．