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Most people feel lonely sometimes, but it usually only lasts between a few minutes and 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 types of loneliness.
The first kind of loneliness is temporary. This is the most common type. It usually disappears quickly and does not require any special attention. The second kind, situation—for example, 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（the opposite of “temporary”）usually lasts more than two years and has no specific cause. People who experience habitual loneliness have problems socializing and becoming 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, for example, 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 similar interests and activities. However, psychologists have found that, though lonely people may have many social contacts, they sometimes feel they should have more. They question their 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 as heart disease, while temporary and situational loneliness can be a sad, and sometimes dangerous condition.
Loneliness and Disease

Three different types of	The most common type is    . It disappears quickly and   no special attention.
The second type is situation, which usually lasts for   than a year.
The      kind is chronic, which means if people experience habitual loneliness, they’ll have problems socializing with others
An important    in loneliness	With the help of Psychologists, we know a person’s social contact is one important factor.
We depend on a wide variety of people for different reasons. For instance, we have interests and activities    to our friends’.
people may have many social contacts, but they sometimes feel they should have more.
The       for finding ways to help the lonely people	One is that they are unhappy and unable to socialize.
The other is that temporary and situational loneliness can be a sad condition, sometimes      too.