Real Academia Española clarifies rules for repeated adverbs

The Real Academia Española (RAE) has clarified a common grammatical doubt regarding the use of commas when repeating adverbs for emphasis. When using reduplication—the linguistic mechanism of repeating a word to intensify its meaning—such as in the phrase “muy muy” to express extreme intensity, a comma should not be used to separate the two words.

While speakers often pause between repeated words during speech, the RAE notes that written Spanish uses commas to organize sentences and facilitate comprehension rather than to mark every spoken pause. Therefore, the correct written form is “muy muy” instead of “muy, muy”.