显微镜下,细胞核的边界清晰可见。Xiǎnwēijìng xià, xìbāo hé de biānjiè qīngxī kějiàn.Under the microscope, the boundary of the cell nucleus is clearly visible.
原子核很小,只有用特殊仪器才能研究。Yuánzǐhé hěn xiǎo, zhǐyǒu yòng tèshū yíqì cái néng yánjiū.The atomic nucleus is tiny and can only be studied with special instruments.
桃子里面的核很硬,小心别咬到。Táozi lǐmiàn de hé hěn yìng, xiǎoxīn bié yǎo dào.The pit inside a peach is hard, so be careful not to bite it.