在美国,有人做过一项调查研究,对满两周岁的儿童作智力测验,过了三年以后,即他们五岁时,再作一次同样的测验,比较孩子两岁和五岁的智力,结果发现,有的孩子智力上升了,有的却下降了;有的没有多大差异。于是研究者又对智力上升及智力下降的孩子做进一步的调查。调查的内容着重孩子受教育的环境,目的是找出在父母的职业、收入、居住地区大体相同的条件下,孩子智力发展快慢的因素。得出的结 In the United States, a survey has been conducted to make intelligence tests on children aged two or above. Three years later, when they were five, the same test was conducted again to compare children’s intelligence of two and five. The results showed that some children’s intelligence rose, while others declined; some did not make much difference. The researchers then further investigation of children with intellectual and intellectual decline. The content of the survey focuses on the educational environment of children, and aims to find out the factors that affect the children’s intelligence development under the same general conditions of their parents’ occupation, income and living area. Drawn knot