after the second world war the improved themselves in 50 years and became one of the most developed countries .
After the Second World War , they improved themselves in 50 years and became one of the most developed countries .
After the Second World War , they improved themselves in 50 years and became one of the most developed countries .
文法上の誤りを修正してください: after the second world war the improved themselves in 50 years and became one of the most developed countries . 出力: