骨干

The older employees are the backbone of the industry.

富有雇员是行业骨干。

In 1998, some cadreman are admitted as shareholder.

1998年，公司将部分骨干吸收为股东。

It’s only really the hard core that bother(s) to go to meetings regularly.

只有那些坚定骨干分子才不怕麻烦定期去开。