[U]
uncountable noun
不可数名词
4A
Anyone Anytime Anywhere Anyway
随时随地任何人
AA
Austroasiatic Language Family
南亚语系
AAT
American Accent Training
美国口音训练
ab
Automated Bibliography
自动书目
ACD
Absolute Cardiac Dullness
绝对心衰
ACEFRS
Arabic, Chinese, English, French, Russian and Spanish
阿拉伯文,中文,英文,法文,俄文和西班牙文