Language proficiency or linguistic proficiency is the ability of an individual to speak or perform in an acquired language. As theories among pedagogues as to what constitutes proficiency go, there is little consistency as to how different organizations classify it. Additionally, fluency and language competence are generally recognized as being related, but separate controversial subjects. In predominant frameworks in the United States, proficient speakers demonstrate both accuracy and fluency, and use a variety of discourse strategies. Thus, native speakers of a language can be fluent without being considered proficient. Native-level fluency is estimated to be between 20,000–40,000 words, but basic conversational fluency might only require as little as 3,000 words.