again ad. 1 重新, 再一次［I enjoyed the book so much that I may read it again. 我太喜欢这本书了，因此我要再读一遍。］ 2 恢复原样，回到原处［She is home again. 她又回到家。］

　　a•gain ● ad.

　　against prep. 1 反对 ［The council is against the proposal. 理事会反对这建议。］2 撞击［She threw the ball against the wall. 她把球扔到墙上。］3 逆，与某个方向或过程相反［It was hard to walk against the wind. 逆风行走很困难。］

　　a•gainst ● prep.

　　agate n. 1玛瑙 2 小孩玩的玻璃弹子

　　ag•ate ● n. (复) agates

　　age ① n. 1 年龄 [She graduated at the age of eighteen.她十八岁毕业。] 2 时期 [Adolescence is often called an awkward age. 青春期常被称作危险期。] 3 老年，老 [The pages of the book were yellow with age. 这本书的书页都旧的发黄了。] 4 时代 [the Stone Age 石器时代；the Space Age 太空时代]-见词条period的词汇选择栏。 5 (常用ages)(非正式用法) 很长一段时间 [ It has been ages since I have seen her. 我好久没见到她了。]

　　② v. 1 变老，变旧 [ Our dog is aging quickly. 我们的狗正迅速衰老。] 2 使变老 [ Hard work has aged him. 辛劳催他年老。]

　　age ① n. (复.) ages ② v. aged, aging

　　aged a. 1 年老的 ［my aged grandmother 我的老祖母］2 ……岁的 ［a pupil aged ten十岁的学生］

　　a•ged ● a.

　　agency n. 1 代理处，代办处［An employment agency helps people find jobs. 职业介绍所帮人找工作。］2 提供特殊帮助的政府部门和其他组织［The social agency gives food and clothing to people in need. 社会局给需要帮助的穷人提供食物和衣服。］

　　a•gen•cy ● n. (复) agencies

　　agent n. 1 原因, 动因［Education is an agent for changing society. 教育能改变社会。］2 代理人, 经纪人，代理商［Most actors hire agents to handle their business. 大多数演员都雇经纪人来处理业务。］

　　a•gent ● n. (复) agents

　　aggravate v. 1 加重，恶化，加剧［Walking will aggravate your sprained ankle. 走路会使你的踝关节扭得更厉害。］ 2 (非正式用法)使恼火，激怒，烦扰 ［The talking in the audience began to aggravate us. 听众的交谈使我们感到恼火。］

　　ag•gra•vate ● v. aggravated, aggravating