1. A machine translation system comprising: a translated text creator for creating a translated text in which an original text in a first language is translated into said translated text in a second language while an unknown word not registered in at least one dictionary is left in said first language; a translated text display for displaying said translated text created by said translated text creator; and a link setter for setting a link for said unknown word in said first language in said translated text displayed by said display for which an instruction is provided, such that a search for said unknown word in said first language is conducted using said unknown word as a search word in a predetermined Internet search engine based on said first language.