1.aluminum n.铝

例:Air pollution from the giant aluminum refinery is killing our plants.

2.alumna n.女校友，女毕业生(a female former student of a school, college or university)

3.alumnus n.男校友，男毕业生(a male former student of a school, college or university)

例:He is an alumnus of Peking University of the class of 1986.

4.amalgam n.混合物( combination)

词根记忆：本义是“汞合金”，该词来自拉丁文amalgama(混合)；联想记忆：am+alg+am，前后两个am结合--混合

例:amalgam of Chinese and Western medicines中西药合剂

派生词:amalgamate(v.合并，联合)：amalgamation(n.混合，合并)

5.amass v.积聚(to gather,accumulate)

词根记忆：a+ mass( -团)--变成--团--积聚

例:While in college, John amassed a shelf of reference books.

派生词:amassment(n.积蓄，聚积)

同根词：massive(a.巨大的)

6.amateur n.业余爱好者(one who practisesa sport or art without receiving money for it one who is unskilled or inexperienced in an activity)

词根记忆：amat( =amor爱)+eur（人)--爱好的人--业余爱好者

例:He is an amateurin boxing.

派生词:amateurish(a.业余爱好的；不熟练的)

同根词：amorous(n.多情的)

7.amber n.琥珀( hard clear yellowish brown gum )

发音记忆：“爱不”--爱不释手的珍物--琥珀

8.ambiguity n.模棱两可，模糊(uncertainty)

词根记忆：ambi(绕着，在什么周围)+guity--围着什么绕来绕去--模棱两可

例:The ambiguityof the teacher's response made us realize he did not know the answer.

9.ambiguous a.意义不明的，模棱两可的( obscure)

例:The professor gave an ambiguous answer to Jane's question.

10.ambitious a.有抱负的，雄心勃勃的( having a desire to achieve a particular goal);宏大的( an idea or plan on a large scale and needs a lot of work to be carried out successfully)

例:Over the last ten years, overcrowding in the prisons of Barraland has essentially been eliminated as a result of an ambitious program of prison construction.

派生词:ambitiously(ad.雄心勃勃地：热切地)

同根词：ambition(n.野心)