Substratum Theory proposes that when learners acquire a new language, they learn imperfectly and pass these imperfections on to future generations.

• A. They imitate perfect models
• B. They erase errors over time
• C. They learn imperfectly and pass them on
• D. Language change is impossible

Answer: (C)

Substratum Theory focuses on how the influence of learners’ first language can shape a language as it develops. It argues that learners do not acquire perfect competence; they bring interference from their L1, producing imperfect forms in the new language. When these imperfect forms are picked up and used by future learners, they can become part of the language and contribute to change over generations. This is exactly what the statement describes: learning imperfectly and passing those imperfections on to future generations. The other ideas don’t fit the theory because they imply flawless learning, the erasure of errors, or deny language change altogether, none of which align with how substratum theory explains linguistic evolution.