Nearly a third of the children were severely underweight.是什么意思？

Nearly a third of the children were severely underweight.

近1/3的孩子体重严重偏轻。

nearly

adv. 几乎，差不多，险乎；

例句
His increasing alignment with the Reagan administration nearly cost him re-election.
与里根政府日益紧密的关系差点让他失去了连任的机会。

third

n. 第三，三分之一，第三档；adj. 第三的，三分之一的；

例句
A third brigade is at sea, ready for an amphibious assault.
还有一个旅已在海上待命，准备两栖进攻。

of

prep. 关于，属于…的，由…制成；aux. 助动词 [非标准用语、方言] =have [主用于虚拟语气]；

例句
He did have a real knowledge of the country...
他对该国的确知之甚多。

the

art. 指已提到的人（物），指说话人与听者已知的人（物），用于独一无二的事物前，与形容词最高级和序数词连用；

例句
He did have a real knowledge of the country...
他对该国的确知之甚多。

children

n. 孩子们(child的复数)，儿童，膝下，孥；

例句
Their permissiveness toward their children reflects the wild abandon of their own lives.
他们对孩子的放任折射出他们自身生活的放浪形骸。

were

be的过去时复数和第二人称单数形式，有时代替 was,用于条件从句、动词 wish 之后等；

例句
Shops, houses, and vehicles were set ablaze.
店铺、房子和车辆全都陷于火海。

severely

adv. 严格地，严重地，严厉地，严肃地；

例句
The accident left the boy severely brain-damaged and almost totally reliant on others.
那次事故使这个男孩脑部严重受损，生活几乎完全依赖别人。