a开头的英语单词数不能准确地给出一个数字，因为每年都会添加新词汇。可以概括在几千到几万。下面列出了一些以a开头的英语单词：
aardvark, abacus, abandon, abate, abbreviate, abhor, abolishment, abominable, abortive, absolute, absolve, abundance, abut,acceptable, access, accessories, acclaim, accident, acclaim, accommodation, accompany, accomplishment, accuracy, accuse, ache, acquire, acrimony, adapt, adept, admirable, adage, adherent, admirable, adieu, advent,aeroplane, afield, affectionate, affirmation, afresh, agape, agree, aim, alarm, alias, alienate, align, alleviate, alloy, alms,altruism, amenable, amendment, amiable, amorous, allot, amuck, anagram, analyze, ancestor, angle, animate, antagonism, antenna,anthropology, appetence, apex, apparel, appellant, appreciate, apprehend, aperture, appropriate, appalling, arbor, ardor, argue, arid, array,arrogant, articulate, artificial, ascend, ascertain, aspiration, assault, assert, asset, assurance, astound, attached, attune, august, auspicious,avarice, avocado, avail.

根据英文单词拼写，可以得到单词有：

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