Learning a second language before age 10 is the only way to achieve native-level fluency, especially for pronunciation and natural grammar. I started Spanish at 13 and still struggle with rolling my r's, while my cousin, who grew up bilingual in Spanish and English, speaks both perfectly. Even though adult learners can become highly proficient, most will always have an accent that marks them as non-native. Do you think early immersion is truly necessary, or can motivated adults bridge that gap with enough practice?