The brain receives information from the outside world through the sensory （感觉的） system．This information is collected through the eyes，the nose，the ears，the mouth and the surface ofthe body．It is then kept in the memory．In fact，scientists do not completely understand how thememory works but they are not sure how much information that the human brain can store．Also，it appears that the information is never lost．Very old people often remember things that happened in their childhood which have not come to their minds for sixty to seventy years．If we have kept something in our memory，it is here．But can we get it out again and use it？That is the difficulty．

Some of the information we receive only goes into the Short Term Memory．We only keep

this information for a minute or two，then we lose it．This temporary （暂时的） memory is veryimportant in our thinking and understanding．It is used，for example，when you try to remember a name that someone told you a moment ago or a telephone number that you are going to dial （拨）．School children in class often seem to use the Short Term Memory if they are not interestedin the subject．When school teachers describe this，they say that things go"in one ear and out inthe other"．But if a child is interested，he puts the information in his Long Term Memory，and henever loses it．Long Term Memory depends heavily on our understanding of the meaning of theinformation we receive．

46．Information is collected through the___of sight，hearing，smell，taste and touch．

A．sense

B．experience

C．practice

D．brightness

47．Very old people can remember something happened___．

A．recently

B．about seventy years ago

C．in their thirties

D．in their classroom

48．If a school child is not interested in a subject，___．

A．he forgets what he learns quickly

B．he memorizes what he learns quickly

C．he forgets what he learns slowly