Six weeks after conception, your baby is the size of your little fingernail.

受孕六周后你的孩子有你小手指甲那么大。

Baby boys do not react at all to the difference and the size of the cube.

男婴对立方体的大小和差异完全没有反应。

Baby boys do not seem to notice the difference in the size of the ball, but girls immediately become excited and begin to make noises that sound like language.

男婴似乎没有注意到球的大小的不同，但女婴立即变得兴奋，并开始发出听起来像是语言的声音。

Still, Dr. Bernstein said the study was strong not just because of its size but because it weighed factors other than malformations, such as birth weight, that also affect the health of the baby.

伯恩斯坦博士还说，这项研究之所以强大，不仅是因为它的规模，还因为它考虑到除畸形以外同样影响婴儿健康的因素，如出生体重。

Baby kangaroos are called joeys and are only the size of your thumb when they're born!

袋鼠宝宝称作“幼兽”，它们刚出生的时候只有拇指大小！