Dấu hỏi

Hook

Diacritics in Latin & Greek
accent
acute( ´ )
double acute( ˝ )
grave( ` )
double grave( ̏ )
breve( ˘ )
inverted breve( ̑)
caron, háček( ˇ )
cedilla( ¸ )
circumflex( ˆ )
diaeresis, umlaut( ¨ )
dot( · )
palatal hook( ̡ )
retroflex hook( ̢ )
hook above, dấu hỏi( ̉ )
horn( ̛ )
iota subscript( ͅ )
macron( ¯ )
ogonek, nosinė( ˛ )
perispomene( ͂ )
overring( ˚ )
underring( ˳ )
rough breathing( ῾ )
smooth breathing( ᾿ )
Marks sometimes used as diacritics
apostrophe( ’ )
bar( ◌̸ )
colon( : )
comma( , )
period( . )
hyphen( ˗ )
prime( ′ )
tilde( ~ )
Diacritical marks in other scripts
Arabic diacritics
Early Cyrillic diacritics
kamora( ҄ )
pokrytie( ҇ )
titlo( ҃ )
Gurmukhī diacritics
Hebrew diacritics
Indic diacritics
anusvara( ं ং ം )
chandrabindu( ँ ఁ )
nukta( ़ )
virama( ् ് ్ ් ್ )
visarga( ः ঃ )
IPA diacritics
Japanese diacritics
dakuten( ﾞ )
handakuten( ﾟ )
Khmer diacritics
Syriac diacritics
Thai diacritics
Related
Dotted circle◌
Punctuation marks
Logic symbols

In typesetting, the hook above (Vietnamese: dấu hỏi) is a diacritic mark placed on top of vowels in the Vietnamese alphabet. In shape it looks like a tiny question mark without the dot underneath. For example, a capital A with a hook is "Ả", and a lower case "u" with a hook is "ủ". The hook is usually written to the right of the circumflex in conventional Vietnamese orthography. If Vietnamese characters are unavailable, it is often replaced by a question mark after the vowel (VIQR encoding).

This diacritic functions as a tone marker, indicating a "mid falling" tone (hỏi): which is "dipping" (˨˩˥) in Southern Vietnamese or "falling" (˧˩) in Northern Vietnamese; see Vietnamese language § Regional variation: Tones. The Southern "dipping" tone is similar to the questioning intonation in English.

Apart from precomposed characters, in multiple scripts, the combining diacritical mark is encoded at U+0309 ̉ combining hook above (HTML ̉)

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Wikipedia