If you do not use your arms or your legs for some time, they will become weak, and when you start using them again, they slowly become strong again. Everybody knows that. Yet many people do not seem to know that memory works in the same way.When someone says that he has a good memory, he really means that he keeps his memory in practice by using it. When someone else says that his memory is poor, he really means that he does not give it enough chance to become strong.If a friend says that his arms and legs are weak, we know that it is his own fault. But if he tells us that he has a poor memory