nucleus|nuclei

原子核由质子和中子组成。

The ___nucleus of an atom consists of protons and neutrons.

这些核心成员构成了我们团队的中坚力量。

These ___nuclei members form the backbone of our team.

科学家们正在研究细胞核中的DNA结构。

Scientists are studying the DNA structure in the ___nucleus.