alive, asleep, aback, abroad, afoot, ashore, ahead, abed, aside

anew, afresh, akin, abreast

abide, arise, awake, ashamed, accursed, allay, affright

adjourn, advance, address, advertisement, adverb, adjective

abysmal, adamant, amethyst, asexual, amoral, agnostic

abaft, ablaut

acet, acetate, acetone, acetonitrile, acetic acid, acetum

acr 当acro后面的第一个字母是元音时，则o去掉，为acr
acrid, acridity, acrimony
acro
acrobat, acromegaly, acronym, acrophobia, acropolis, acrostic

actin 有时当actino-后面的第一个字母是元音时，则i去掉，为actin-
actinic, actinium
actino
actinomycete, actinomycetes, actinomycin, actinobacteria

ad
adage, adagio, add, adjective, adore, adorn, adult, adverb, advertise
ac-, af-, ag-, al-, as-, at-, ap-, ar。由ad-简化为a-，因为a是元音，当偶到辅音时，辅音要双写
access, account
affection
aggression
appear, appetite, apply, appoint, approve
arrange, arrest, arrive, arrow

adenosine, adenocarcinoma, adenoma, adenovirus, adenoid

aero, aerobic, aerospace, aerosol, aeroplane

aetio
aetiology, aetiological, aetiologic, aetiohemin
etio
etiology, etiological, etiologic, etiologies

afro, Africa, African

allopathy, allotropy, allocentric

alti
altimeter, altitude
alto 当形容“云”时，用alto-
altostratus, altocumulus

amb 有时当ambi 后面的第一个字母是元音时，则i去掉，为amb
ambagious, ambassador, ambulance, ambulant, ambulate, ambulation, ambulatory
ambi
ambidexterity, ambidextrous, ambience, ambient, ambiguous, ambit, ambition, ambitious, amble
am, an
amputate, amputation, ancillary, andante, anfractuous

America, american, americans, americas, americologue

amine, aminotransferase, aminoglycoside

amph 有时当amphi 后面的第一个字母是元音时，则i去掉，为amph
amphora
amphi
amphibian, Amphictyonic, amphisbaena, Amphiscians, amphitheater

amyl 有时当amylo 后面的第一个字母是元音时，则o去掉，为amyl
amyl, amylase
amylo
amyloid, amylose, amyloidosis, amylopectin, amyloplast

annex,announce,annihilate

annul;aught

Anabaptism, Anabaptist, anabasis, anabolic, anachronism, Anacreontic, anacrusis, anadiplosis, anadromous, anagnorisis, anagogical, anagram, analects, analemma, analepsis, analeptic, analogous, analogue, analogy, analysis, analytic, analytical, analytics, anamnesis, anamorphosis, ananym, anaphase, anaphora, anaphylactic, anasarca

androgynous, androgyny, android, andron, androgen

anemometer, anemometry, anemograph, anemone

angiogenesis, angiogram, angiography, angiogenic, angiotensin

anisotropic, anisotropy

anomaly, anomalous, anomalously, anomalousness, anomalies

antecede, antecedent, antedate, antediluvian, anterior

anthrop- 有时当anthropo- 后面的第一个字母是元音时，则o去掉，为anthrop-
anthropic
anthropo-
anthropocentric, anthropology, anthropomorphous, anthropogeny, anthropoid, anthropolatry, anthropometry, anthropopathy, anthropophagous, anthropophagy, anthropophobia

ant- 有时当anti- 后面的第一个字母是元音时，则i去掉，为ant-
antacid, antagonism, antagonist, antagonize, antalgic, antanaclasis, antaphrodisiac, antarctic, antephialtic, anthelion
anti-
antic, anticipate, anticipation, antique;

ap- 有时当apo- 后面的第一个字母是元音时，则o去掉，为ap-
apagoge, apanthropy, aperitif, aperitive, aperture
apo-
apocalypse, apocrypha, apodictic, apodyterium, apogee

aqu- 有时当aqua- 后面的第一个字母是元音时，则a去掉，为aqu-
aqueous, aquifer
aqua-
aqualung, aquamarine, aquanaut, aquarelle, aquarium, Aquarius, aquatic, aquatint, aquaculture, aquacade

archaebacteria, archaeoastronomy, archaeology, archaeologist, archaeopteryx, archaeocyte

aristocrat, aristocratic, aristocracy

arteri- 有时当arterio- 后面的第一个字母是元音时，则o去掉，为arteri-
arterial
arterio-
arteriosclerosis, arteriole, artery, arteriovenous

arthr- 有时当arthro- 后面的第一个字母是元音时，则o去掉，为arthr-
arthralgia, arthritis
arthro-
arthropod, arthroscopy

atelectasis, atelomyelia, ateloencephalia, atelocardia

atmos, atmosphere, atmospheric

audio, audiology, audiophile, audiotape, audiovisual

Austria, austronesian, austro-hungarian, austroasiatic, austronesia