Language proficiency in the UPSC Civil Services Examination is primarily evaluated through the language paper, where candidates choose their preferred language from an extensive list. The examination tests various language skills, including comprehension, grammar, and expression. Candidates must demonstrate their ability to articulate thoughts clearly and accurately in written format. Furthermore, essays and answers in other papers may also reflect language proficiency; thus, strong communication skills in at least one language can greatly benefit candidates in expressing their ideas effectively throughout the examination.