In Portuguese, the most frequent crasis is the contraction of the preposition a ("to" or "at") with the feminine singular definite article a ("the"), indicated in writing with a grave accent. For example, instead of *Vou a a praia ("I go to the beach"), one says Vou à praia ("I go to-the beach"). This contraction turns the clitic a into the stressed word à.
Crasis also occurs between the preposition a and demonstratives: for instance, when this preposition precedes aquele, aquela (meaning "that one", with different genders) or aqueles, aquelas (plural), they contract to àquele, àquela, àqueles, àquelas. In this case, the accent marks a secondary stress.
In Greek, the articles το and τα undergo a crasis with various words:
In addition, και undergoes a crasis with the first-person singular pronoun:
When writing with breathing marks, the breathing mark is placed on one of the vowels resulting from crasis; this is the only case in which a breathing mark is placed on a vowel when the first letter is a consonant.