So when can someone say they “speak” a language? That’s the million-dollar question. Can someone consider themselves a Spanish speaker if they’re conversational but often can’t understand native speakers because they “talk too fast”? If they use only two verb tenses and every sentence contains mistakes?

The answer may be less “yes/no” and more “how well?”

Luckily, scales for measuring spoken fluency and overall proficiency exist. “Fluency is an abstract concept, so we assign observable variables,” explains Daniel Morgan. Two of the most reliable factors are “speech rate” and “utterance length”. Speech rate can be defined as how much (effective) language you’re producing over time, for example how many syllables per minute. Utterance length is, as an average, how much you can produce between disfluencies (e.g. a pause or hesitation). You could look at accuracy as being subsumed into fluency, in terms of grammatical accuracy, lexical choice, pronunciation, and precision.”

De Jong describes the unconscious process any speaker goes through before speaking: conceptualising what to say, formulating how to say it, and, finally, articulating the appropriate sounds. All of this takes place in roughly six syllables per second. A speaker of a second language who needs to convert their thoughts into an unfamiliar language faces an even greater challenge in meeting these strict time constraints. They must also often overcome inhibition and pronunciation challenges. Accuracy may still be lacking at this stage, but make no mistake – achieving L2 fluency is a colossal feat.

The Council of Europe’s Common European Framework of References (CEFR) for Languages groups language learners into concrete proficiency levels, where fluency and accuracy are just two of many examined criteria. The CEFR – available in 40 languages – divides proficiency into six “can do” levels – A1, A2, B1, B2, C1, and C2. A corresponds to “Basic” levels, B to “Independent”, and C to “Proficient.” Observable skills include:

A1: Capabilities range include basic introductions and answering questions about personal details provided the listener speaks slowly and is willing to cooperate.

A2: Can describe in simple terms aspects of his/her past, environment and matters related to his/her immediate needs and perform routine tasks requiring basic exchanges of information.

B1: Can deal with most daily life situations in the country where the language is spoken. Can describe experiences, dreams and ambitions and give brief reasons for opinions and goals.

B2: Can understand the themes of complex texts on both concrete and abstract topics and will have achieved a degree of fluency and spontaneity, which makes interaction with native speakers possible without significant strain for either party.

C1: Can understand a wide range of longer texts and recognise subtleties and implicit meaning; producing clear, well-structured and detailed text on complex subjects, showing controlled use of organisational patterns, connectors and cohesive devices.

C2: Can understand virtually everything heard or read, expressing themselves spontaneously, very fluently and precisely, while differentiating finer shades of meaning even in highly complex situations.

Geraint Thomas, a Cambridge English speaking exam team leader, explains: “We look at things like cohesion, response rate, discourse management, and pronunciation, but each variable has sub-variables. You can break pronunciation down into stress and individual sounds.” He emphasises that the progression is gradual. “You can expect a good B2 candidate to have certain things under control; the present tense, maybe. However, they might not have their second conditional, and you’re aware that this is a progressive thing.”