The grave accent may be used on e and o when they represent open-mid vowels.

Single and represent both their single and long vowels, since they rarely contrast.

This script had no characters representing vowels.

With the introduction of letters representing vowels in the Greek alphabet, the need for inter-word separation became much less.

They can represent vowels, consonant doubling, or nasal sound.

The breve, together with the circumflex and horn, are used in the Vietnamese language to represent additional vowels.

Hebrew has many various diacritic marks known as niqqud that are used above and below script to represent vowels.

Others letters represent vowels or vowel combinations which have certain tones.

This is the regular way to represent "long" vowels in the last syllable of a morpheme.

Guangdong romanization makes use of diacritics to represent certain vowels.