New research from Massachusetts Institute of Technology (MIT) suggests that if people want to achieve native-like proficiency in new language, they should start learning that language before age of ten. researchers added that children up to age of 17 or 18 remain adept at learning grammar. There is bad news for those who want to pick up new language beyond their late teens. The researchers say this is past "critical period" when language-learning ability starts to decline. Researcher Joshua Hartshorne said: "As far as child is concerned, it's quite easy to become bilingual....That's when you're best at learning languages. It's not really something that you can make up later."
research was based on analysis of results from 10-minute online grammar quiz. Over 670,000 language learners of all ages participated in test. Researchers measured grammatical ability of people who started learning language at different points in their life. Professor Hartshorne focused on grammar rules that were most likely to confuse non-native speaker as gauge of that person's proficiency. MIT researcher Josh Tenenbaum suggested people simply might be too busy to learn language later in life. He said: "After 17 or 18, you leave home, you work full time, or you become specialized university student. All of these might impact your learning rate for any language.