At the A1 (Beginner) level, learners make frequent errors with basic structures, such as

word order, subject-verb agreement, and simple tenses. Pronunciation is often unclear,

making communication difficult for native speakers.

At the A2 (Elementary) level, learners struggle with more complex structures, making

errors with verb forms, prepositions, and question forms. Pronunciation is still developing,

and more complex sounds or intonation patterns may be challenging.

By B1 (Intermediate), learners can manage routine tasks but still make errors with tenses,

articles, and word choice. Pronunciation is generally understandable, though occasional

mispronunciations may occur.

At B2 (Upper Intermediate), errors are less frequent but still occur with more complex

structures, such as conditionals, passive voice, and perfect tenses. Pronunciation is mostly

clear, though slight accents or occasional difficulties with complex words may remain.

By C1 (Advanced), learners rarely make mistakes, but occasional errors may happen with mixed conditionals, relative clauses, or advanced vocabulary usage. Pronunciation is very close to native-like, with only minor errors or slight accents.

At C2 (Proficient), grammar errors are almost nonexistent. Any mistakes tend to be with

very complex sentence structures or rare nuances, such as choosing between advanced

synonyms or subtle differences in meaning. Pronunciation is virtually identical to that of

native speakers, with no significant errors or accent.