Doctors have long known that breast-feeding can be good for a baby's health. This is especially true in poor countries, where water can be contaminated. For instance, a baby given formula in developing countries is 14 times more likely to die in the first six months than one who's breast-fed. In the U.S., some research has suggested that breast-feeding may boost a baby's IQ（智商）by a few points. But a recent study with siblings（兄弟姐妹）found little advantage to breast-feeding.

词汇积累：

be good for 对……有好处

especially adv.特别地（副词，可修饰形容词或动词）

contaminate v.弄脏，污染

for instance 比如

formula n.配方（文中指非母乳喂养）

be likely to 倾向于，容易

suggest v.建议（常用动词）

boost v.提高

长句分析：

For instance, a baby given formula in developing countries is 14 times more likely to die in the first six months than one who's breast-fed.

主语a baby，谓语is likely to

句子中存在一个比较关系，a baby given formula非母乳喂养与one who's breast-fed母乳喂养

大意：比如，在前六个月，发展中国家非母乳喂养婴儿的死亡率是母乳喂养的14倍。

常考考点分析：

In the U.S., some research has suggested that breast-feeding may boost a baby's IQ（智商）by a few points. But a recent study with siblings（兄弟姐妹） found little advantage to breast-feeding.

在阅读理解题中，关联词是关键，尤其这里出现but，是一个明显的转折，第一句breast-feeding may boost a baby's IQ（智商）母乳喂养可能提高智商，第二句转折，found little advantage to breast-feeding母乳喂养在（提高智商方面）并没有什么优势。第二句是答题的关键。