If a child’s IQ is measured with the Wechsler Intelligence Scale and is between 70 and 90, he is in a borderline state, he has neither reached a normal level of intelligence nor is he mentally retarded, it is due to a mild disorder in the development of the brain, which affects some of the higher mental activities of the brain, for example, in abstract thinking ability, comprehension, organization, language expression, etc. than For example, the development of abstract thinking, comprehension, organization, and language skills is slower than normal children, and the effectiveness of learning is affected to a certain extent. For example, pre-eclampsia miscarriage, asphyxia, forceps delivery, and emotional stress during pregnancy can affect the neurological development of the child’s brain. In the way of later nurturing, parents leave their children to the elderly or nannies, with little scientific training for the children, and some even do not send their children to kindergartens and preschools, so that the children lose to other children at the starting line. Some parents, on the contrary, take care of their children because they think they are weak in various aspects. Some children are still too old to tie their own shoelaces or wipe their bottoms, and parents keep an eye on them when they do their homework, even teach them by hand, do questions instead of them, and easily tell them ready-made answers. This causes children to be dependent and lack self-confidence and independence. Some parents train their children even less in motor coordination, they are clumsy and procrastinate, and they can’t reach the standard in sports, which will directly affect the development of their children’s learning ability, but parents don’t realize it. These children need more care and help from teachers and parents, but not pampering and overprotection, let alone giving up regardless. Some parents, when they see that their child’s IQ test results are below normal, think that there is nothing they can do, that their child is just like that, and that they can just get a certificate from the hospital to give to the school, and some schools and teachers have the same attitude. A child’s intelligence level is not constant until adulthood, 50% is determined by genetics, 50% is determined by the acquired environment. The general brain nervous system does not stop developing until the age of 25. If you can get 100 IQ points at the age of 17, 50 points are obtained before the age of 5, 30 points can be obtained between the ages of 5 and 8, and 20 points can be obtained between the ages of 8 and 17, but it must be developed and improved through scientific training, and the earlier the training, the better.