People appear to born to compute. The numerical skills of children develop so early and so inexorably that it is easy to imagine an internal clock of mathematical maturity guiding their growth. Not long after learning to walk and talk, they can set the table with impress accuracy---one knife, one spoon, one fork, for each of the five chairs.
Soon they are capable of nothing that they have placed five knives, spoons and forks on the table and, a bit later, that this amounts to fifteen pieces of silverware. Having thus mastered addition, they move on to subtraction. It seems almost reasonable to expect that if a child were secluded on a desert island at birth and retrieved seven years later, he or she could enter a second enter a second-grade mathematics class without any serious problems of intellectual adjustment.
Of course, the truth is not so simple. This century, the work of cognitive psychologists has illuminated the subtle forms of daily learning on which intellectual progress depends. Children were observed as they slowly grasped-----or, as the case might be, bumped into----- concepts that adults take for quantity is unchanged as water pours from a short glass into a tall thin one.
Psychologists have since demonstrated that young children, asked to count the pencils in a pile, readily report the number of blue or red pencils, but must be coaxed into finding the total. Such studies have suggested that the rudiments of mathematics are mastered gradually, and with effort. They have also suggested that the very concept of abstract numbers------the idea of a oneness, a twoness, a threeness that applies to any class of objects and is a prerequisite for doing anything more mathematically demanding than setting a table-----is itself far from innate
2017届高考英语一轮复习课时作业:unit 22 Environmental Protection(北师大版)
2017届高考英语一轮复习限时训练:6-5 The power of nature(新人教版)
2017届高考英语一轮复习限时训练:7-1 Living well(新人教版)
2017届高考英语一轮复习课时作业:unit 17 Laughter(北师大版)
2017届高考英语一轮复习课时作业:unit 21 Human Biology(北师大版)
2017届高考英语一轮复习课时作业:unit 18 Beauty(北师大版)
2017届高考英语一轮复习课时作业:unit 11 The Media(北师大版)
2017届高考英语一轮复习限时训练:6-4 Global warming(新人教版)
2017届高考英语一轮复习限时训练:4-1 Women of achievement(新人教版)
2017届高考英语一轮复习限时训练:2-4 Wildlife protection(新人教版)
2017届高考英语一轮复习限时训练:4-4 Body language(新人教版)
2017届高考英语一轮复习课时作业:unit 15 Learning(北师大版)
2017届高考英语一轮复习限时训练:4-2 Working the land(新人教版)
2017届高考英语一轮复习限时训练:5-4 First aid(新人教版)
2017届高考英语一轮复习限时训练:1-4 Earthquakes(新人教版)
2017届高考英语一轮复习限时训练:3-4 Astronomy :the science of the stars(新人教版)
2017届高考英语一轮复习课时作业:unit 23 Conflict(北师大版)
2017届高考英语一轮复习限时训练:1-3 Travel journal(新人教版)
2017届高考英语一轮复习限时训练:2-5 First aid(新人教版)
2017届高考英语一轮复习限时训练:6-3 A healthy life(新人教版)
2017届高考英语一轮复习限时训练:5-3 Life in the future(新人教版)
2017届高考英语一轮复习限时训练:1-5 Nelson Mandela-a modern hero(新人教版)
2017届高考英语一轮复习限时训练:6-2 Poems(新人教版)
2017届高考英语一轮复习限时训练:3-1 Festivals around the world(新人教版)
2017届高考英语一轮复习限时训练:2-2 The Olympic Games(新人教版)
2017届高考英语一轮复习限时训练:4-5 Theme parks(新人教版)
2017届高考英语一轮复习限时训练:6-1 Art(新人教版)
2017届高考英语一轮复习限时训练:2-1 Cultural relics(新人教版)
2017届高考英语一轮复习课时作业:unit 14 Careers(北师大版)
2017届高考英语一轮复习限时训练:7-5 Travelling abroad(新人教版)
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