下面短文中有10处语言错误。请在有错误的地方增加、删除或修改某个单词。
增加：在缺词处加一个漏字符号（∧），并在其下面写上该加的词。
删除：把多余的词用斜线（＼）划掉。
修改：在错的词下划一横线，并在该词下面写上修改后的词。
注意：1、每处错误及其修改均仅限一词；
2、只允许修改10处，多者（从第11处起）不计分。
Though a great progress has been made in science these years, there are still many people live in poor conditions. They make their lives by collecting and selling used thing. Their children cannot go to school because they have not enough money to send their children to there. Why you think so many people still suffer from poverty now? The answer lies on the population explosion. A president of a developing country once said; “It is us who are to blame for the poverty because we used to produce child without limit.” Although this few words sound simple enough, they have clear pointed out one of the causes of the population explosion.