請問「中樓底柱」或「中堅分子」既英文應該點寫呀?

中流砥柱 中堅份子

mainstay

e.g. Liza Wang is a TVB mainstay.

hard core, backbone

e.g. He a member of the hard core of the student union.

2006-11-09 15:33:03 補充：
打漏字 He is a member of the hard cord of the student union. hard core 是指一群中堅份子, 同team一樣用單數眾數也可, 但不可以用 a hard core 來指一個具有中堅身份的人

Kingpin or linchpin.

You may use the -soul- of xx.

implying without the soul, the thing will not work