information:highlighting, information:extraction, linguistic:paraphrasing, stylistic:style_transfer
Complications

Some exceptions to the simple genetic relationship model of languages include language isolates and mixed, pidgin and creole languages.

Mixed languages, pidgins and creole languages constitute special genetic types of languages. They do not descend linearly or directly from a single language and have no single ancestor.

Isolates are languages that cannot be proven to be genealogically related to any other modern language. As a corollary, every language isolate also forms its own language family — a genetic family which happens to consist of just one language. One often cited example is Basque, which forms a language family on its own; but there are many other examples outside Europe. On the global scale, the site Glottolog counts a total of 423 language families in the world, including 184 isolates.