whereas compra 's/he buys/is buying' does not: comprò la pasta 's/he bought the pasta' but compra la pasta 's/he buys/is buying the pasta'. In addition to language-internal development, fortition can also occur when a language acquires loanwords. Goidelic languages frequently display fortition in loanwords as most initial fricatives (except for , and ) are disallowed in the citation form of Goidelic words. Thus initial fricatives of loanwords are strengthened to the corresponding unlenited variant or the nearest equivalent if the fricative is not part of the phoneme inventory. Examples from Scottish Gaelic: Post-nasal fortition Post-nasal fortition is very common in Bantu languages. For example, Swahili and become after a nasal prefix, and becomes ; voiceless stops become aspirated. In Shambala, and become , and and become and as well. In Bukusu, and become , becomes , and become . In other languages, voiceless fricatives become affricates ; see for example Xhosa. This is similar to the epenthetic stop in words like dance () in many dialects of English, which effectively is fortition of fricative to affricate . See also Consonant mutation Final-obstruent devoicing Grimm's law Historical linguistics Sesotho nasalization References Crowley, Terry. (1997) An Introduction to Historical Linguistics. 3rd edition. Oxford University Press. Phonology Linguistic morphology