N11 has seen three successive generations of star birth, each occurring farther from the center of the nebula.
N11已经连续3代地诞生恒星，每一代都发生远离该星云的中心处。
2
The most educated women, those with bachelor's degrees or higher, are among the most likely never to have given birth, according to the Pew Research Center.
根据皮尤研究中心的调查，在大多数受过教育的女性中，那些具有学士或以上学位者最有可能从未生育。
3
Their mother gave birth to triplets at the center, and two have survived in good condition.