Group + 当中
当中 (dāngzhōng) means "among" or "in the middle of" a group. It is placed after a noun referring to a group of people or things to specify that something exists or happens within that group.
这些学生当中,她的成绩最好。
Zhèxiē xuéshēng dāngzhōng, tā de chéngjì zuì hǎo.
Among these students, she has the best grades.
我们当中有几个人去过日本。
Wǒmen dāngzhōng yǒu jǐ gè rén qù guò Rìběn.
A few of us have been to Japan.
所有候选人当中,他最有经验。
Suǒyǒu hòuxuǎnrén dāngzhōng, tā zuì yǒu jīngyàn.
Among all the candidates, he has the most experience.