[[Loanword|Borrowings]] or [[false cognate]]s can skew or obscure the correct data.<ref>{{harvnb|Lyovin|1997|pp=3–5}}.</ref> For example, English ''taboo'' ({{IPA|[tæbu]}}) is like the six Polynesian forms because of borrowing from Tongan into English, not because of a genetic similarity.<ref>{{cite encyclopedia|url=http://dictionary.reference.com/browse/taboo|encyclopedia=Dictionary.com|title=Taboo}}</ref> That problem can usually be overcome by using basic vocabulary, such as kinship terms, numbers, body parts and pronouns.<ref>{{harvnb|Lyovin|1997|p=3}}.</ref> Nonetheless, even basic vocabulary can be sometimes borrowed. [[Finnish language|Finnish]], for example, borrowed the word for "mother", ''{{lang|fi|äiti''}}, from Proto-Germanic *aiþį̄ (compare to [[Gothic language|Gothic]] ''{{lang|got|aiþei''}}).<ref>{{harvnb|Campbell|2004|pp=65, 300}}.</ref> [[English language|English]] borrowed the pronouns "they", "them", and "their(s)" from [[Old Norse language|Norse]].<ref>{{cite encyclopedia|url=http://dictionary.reference.com/browse/they|encyclopedia=Dictionary.com|title=They}}</ref> [[Thai language|Thai]] and various other [[East Asian languages]] borrowed their numbers from [[Chinese language|Chinese]]. An extreme case is represented by [[Pirahã language|Pirahã]], a [[Muran languages|Muran language]] of South America, which has been controversially<ref>{{cite journal|last1=Nevins|first1=Andrew|first2=David|last2=Pesetsky|first3=Cilene|last3=Rodrigues|year=2009|url=http://www.people.fas.harvard.edu/%7Enevins/npr09.pdf|url-status=dead|archive-url=https://web.archive.org/web/20110604103305/http://www.people.fas.harvard.edu/~nevins/npr09.pdf|archive-date=4 June 2011|title=Pirahã Exceptionality: a Reassessment|journal=Language|volume=85|issue=2|pages=355–404|doi=10.1353/lan.0.0107|citeseerx=10.1.1.404.9474|hdl=1721.1/94631|s2cid=15798043}}</ref> claimed to have borrowed all of its [[pronoun]]s from [[Nheengatu language|Nheengatu]].<ref>{{harvnb|Thomason|2005|pp=8–12 in pdf}}; {{harvnb|Aikhenvald|1999|p=355}}.</ref><ref>"Superficially, however, the Piraha pronouns don't look much like the Tupi–Guarani pronouns; so this proposal will not be convincing without some additional information about the phonology of Piraha that shows how the phonetic realizations of the Tupi–Guarani forms align with the Piraha phonemic system." [http://www-personal.umich.edu/~thomason/papers/pronborr.pdf "Pronoun borrowing" Sarah G. Thomason & Daniel L. Everett University of Michigan & University of Manchester]</ref>
