A-1

('a' in the first tone)

Even in Chinese, which has the letters / morphemes  'e' and  'i' (written usually 'yi') as a single vowel sound words, the single vowel sound 'a' is not a word, but just a sound, which, however, is extensively used in sentences to make questioning or surprised sounds. There are only two character representations for 'a' sounds, 阿 and 啊. The mouth radical, 口, in the left part of a character usually indicates that this character is spoken in the same way as the character without the mouth radical, but does not have that character's meaning.

阿 = this character often stands as a representation of the Roman letter 'a' or the Greek letter 'alpha'; in Chinese, it doesn't mean much by itself, but it is part of a number of originally Chinese two-character words; it is also used when foreign words are written with Chinese characters.

阿姨 = a(1)yi(2) = aunt, polite address form for a housemaid

阿门 = a(1)men(2) = the 'Amen' with which Christians end prayers

东革阿里 = dong(1)ge(2) a(1)li(3) = tongkat ali (a Malaysian and Indonesian testosterone-enhancing herbal); obviously, as a non-Chinese term, one would not have to use the tones associated with the characters that represent this word.

Similar character:

可 = ke(3) = can

Usual form:

可以 = ke(3)yi(3) = can