The document provides an overview of different models for categorizing speakers of English based on whether it is their native, second, or foreign language. It discusses Kachru's three circles model of inner circle (traditional bases), outer circle (former colonies), and expanding circle (other countries). It notes difficulties with these models and proposes some alternatives, including based on competence rather than geography. Sound samples from different English speakers are then provided to test whether the listener can identify a native versus non-native speaker.