(noun.) an active and efficient cause; capable of producing a certain effect; 'their research uncovered new disease agents'.
(noun.) a businessman who buys or sells for another in exchange for a commission.
(noun.) a representative who acts on behalf of other persons or organizations.
(noun.) any agent or representative of a federal agency or bureau.
(noun.) a substance that exerts some force or effect.
安娜校对
以斯拉录入