Children learn language effortlessly and completely voluntarily. They learn new words miraculously fast. A teenager masters about 60,000 words of their mother tongue by the time they finish high ...

The AI program was way less cute than a real baby. But like a baby, it learned its first words by seeing objects and hearing words. Some ideas of language learning hold that humans are born with ...

Corrected: An earlier version of this story incorrectly identified the tiers associated with challenging words. Children who enter kindergarten with a small vocabulary don’t get taught enough ...