The critical period refers to the specific age stage when it is easiest to learn and master certain knowledge, skills and actions. The word critical period was put forward by Austrian zoologist Lorenz in the experimental study of animal psychology. The word "critical period" has laid a certain theoretical foundation for early education. Explain that children learn easily and quickly, and get twice the result with half the effort. But if you miss the critical period, you will spend a lot of energy and time, and get twice the result with half the effort. So, what is the critical period for children to learn? Six months after birth is the key period for babies to learn to chew and feed dry food. 2 ~ 3 years old is the key period for the development of counting ability (oral calculation, physical number, physical number, total number of words). 2 ~ 3 years old is the first critical period for learning oral English, and about 5 years old is the second critical period for oral English development. Two and a half years old to three and a half years old is a crucial period for educating children to abide by the code of conduct. About 3 years old is a crucial period to cultivate their independent living ability. 3 ~ 5 years old is the key period to develop musical ability. 3 ~ 8 years old is a critical period for learning a foreign language. Before the age of 4, it is a critical period for the development of image vision. About 5 years old is a critical period for the development of the concept of numbers. American psychologist Bloom pointed out through research that if the intelligence measured at the age of 17 is set to 100%, then 50% of it will happen before the age of 4, 30% between the ages of 4 and 8, and 20% between the ages of 8 and 17. If the mental development of 0 ~ 4 years old is slow, then the mental development will be slow in the future, and the intelligence level will be flat until the peak of 17 ~ 18 years old. Indian "Wolf Child" kamala came into this world at the age of 7-8. Although he was cared for by professionals for six years, he only learned to walk. He didn't learn a dozen words until 17, and his IQ only reached the level of a four-year-old child. Explain that if he misses the key educational opportunity, it will cause irreparable consequences. Therefore, parents must seize the critical period when educating their children. For example, 2-3 years old is the first critical period for learning spoken English. At this time, they should let their children learn pronunciation, speak English, learn nursery rhymes and learn foreign languages.