translation.en: So by comparing how similar GCSE results are in identical twins versus non-identical twins, and doing some clever math, we can an idea of how much variation and performance is due to the environment and how much is due to genes.
translation.zh: 因此，通过比较同卵双胞胎 与异卵双胞胎的 GCSE的成绩， 做一些巧妙的计算后， 我们就可以知道有多少 表现和差异来自环境， 有多少是受基因的影响。