chairman

主席、会长

The chairman opened the meeting with a short welcome speech.

主席以一段简短的欢迎词开场。

董事长

The chairman of the board resigned after a series of losses.

在一连串亏损之后，董事长辞职了。

系主任、主任委员

She served as chairman of the history department for six years.

她担任历史系系主任六年。

主持、担任主席少用

He chairmanned the committee through its most difficult year.

他在委员会最艰难的一年里担任主席。