At the C1 CEFR level, a language learner:
- Can understand a wide range of demanding, longer clauses, and recognize implicit meaning.
- Can express ideas fluently and spontaneously without much obvious searching for expressions.
- Can use language flexibly and effectively for social, academic, and professional purposes.
- Can produce clear, well-structured, detailed text on complex subjects, showing controlled use of organizational patterns, connectors, and cohesive devices.