As the world becomes more globalized and bilingualism is more than just a fun party game, it is perhaps the most useful real-world skill ever. If you're considering making the effort to learn a foreign language rather than waiting for the world to adapt to your monolingualism, you're a rare breed indeed. Learning a foreign language is about learning to really communicate and connect with others – an incredibly important life skill that can only be developed through human interaction. When you master a foreign language, you can use your new superhuman power of understanding what someone is saying, remembering the correct vocabulary and grammar, putting that word and grammar into the right context, and responding.
The older you get, the more difficult it is to learn to speak a foreign language. But no one knows exactly what the stopping point is – for example, at what age it becomes difficult to pick up noun-verb agreement in a new language. In one of the largest linguistic studies ever conducted – a viral internet survey of two-thirds of a million respondents – showed that children are proficient at learning a second language by age 18, about 10 years later. But the research also showed that if you want to achieve the grammatical fluency of a native speaker, it's best to start at age 10.
To analyze this problem, other psychologists have collected data on language proficiency and time spent learning English. The researchers estimated that more than half a million people would be needed to fairly estimate when the "critical period" for reaching the highest levels of grammatical fluency would end. Thus, conducting research in this field has become the most relevant topic of recent times.
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