That experience influences subsequent behavior. is evidence of an obvious but nevertheless remarkable activity called 'remembering'. Learning could not occur without the function popularly named memory. Constant practice has such an effect on memory like to lead【M1】______ to skillful performance on piano, to recitation of a poem, and even to【M2】______ reading and understanding these words. So-called intelligent behavior. demands memory, remembering is a primary requirement for【M3】______ reasoning. The ability to solve any problem or even to recognize that a problem exists depends on memory. Typically, the decision to cross a street is based on remembering many early experiences.【M4】______ Practice tends to build and maintain memory for a task or for any learned material. Over a period of no practice which has been【M5】______ learned tends forgotten; and the adaptive consequences may not seem to be obvious. Besides, dramatic instances of sudden forgetting can be seen【M6】______ to be adaptive. In this sense, the ability to forget can be interpreted to【M7】______ having survived through a process of natural selection in animals. Indeed, when ones memory of an emotionally painful experience leads to serious anxiety, forgetting may produce relief. Nevertheless, an evolutionary interpretation might make them difficult to【M8】______ understand how the commonly gradual process of forgetting survived natural selection. In thinking the evolution of memory together with all its possible【M9】______ aspects, it is helpful to consider what would happen if memories failed to fade. Forgetting clearly aids orientation in time, since old memories weaken and the new tend to stand out, providing with【M10】______ clues for inferring duration. 【M1】