Researchers have successfully carried out the process of giving birth to a baby using a controversial "three-parent baby" technique.

研究人员利用一项备受争议的“三亲婴儿”技术，成功实现了生育一名婴儿的过程。

youdao

I was bringing up my three children as a single parent.

我当时作为一个单亲家长抚养着我的3个孩子。

《柯林斯英汉双解大词典》

First, move up three levels to the parent.

首先，将三个层次移动到父层次上。

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Human genes are normally organized along forty-six chromosomes in our cells, twenty-three from each parent.

VOA: special.2009.09.09

British children brought up in two-parent families where only one parent works are almost three times more likely to be poor than children with two parents at work.

ECONOMIST: Women in the workforce

Lone-parent poverty can be tackled in three main ways.

ECONOMIST: Tony Blair��s big idea

Households were more likely to practice all three if they were white, if they were two-parent families, if the mother wasn't obese, if the mother had a bachelor's degree, or if the household income was higher.

CNN: How to fight childhood obesity in 3 steps