(a) (in the habit of) doing things; energetic （惯於）做事的; 精力旺盛的; 积极的; 活跃的: Although he's quite old he's still very active. 他虽然老了, 可仍闲不住. * lead an active life, ie one full of activity 过着活跃的生活 * She takes an active part (ie is energetically involved) in local politics. 她积极参加本地的政治活动. (b) quick; lively 迅速的; 活跃的: have an active brain 头脑灵活. 
functioning; in operation 起作用的; 操作中的: an active volcano, ie one that erupts occasionally 活火山. 
having an effect; not merely passive 有效的; 主动的: the active ingredients 有效成分 * active resistance 积极抵抗. 
radioactive 放射性的. 
(grammar) of the form of a verb whose grammatical subject is the person or thing that performs the action, as in He was driving the car and The children ate the cake 主动语态的（动词的一种形态, 其语法上的主语为施动的人或物, 如 He was driving the car及The children ate the cake等句）. Cf 参看 passive.> active n [sing] (also active voice) (grammar) active(5) forms of a verb 动词的主动语态形式: In the sentence `She cleaned the car' the verb is in the active. 在She cleaned the car句中, 动词是主动式. Cf 参看 passive voice (passive).
actively adv: actively involved in the project 积极参与该计划 * Your proposal is being actively considered. 你的建议正获积极考虑.
activeness n [U].
# active `service (US also active `duty) full-time service in the armed forces, esp during a war 现役: be on active service 服现役.
active voice