By the way, what is the performance of people with low IQ?

Children with mental retardation generally have the following manifestations: 1, eyes hanging obliquely, wide eye distance, flat nose, high chin and tongue sticking out. 2, the skull is square, the gap is hand, the brain volume is small, the head circumference is particularly large, and the head with microcephaly is particularly small. 3. It takes longer to lie down, look up, sit, stand and walk than ordinary children, and it takes longer to hold things by hand. 4, learning to speak late, early teasing without sound response, often 3 ~ 4 years old to start talking, and some even 5 ~ 6 years old can not speak. 5, visual difficulties, inflexible eye movements, dull eyes. 6. Poor hearing ability and no response to sound. Six months later, I still can't tell the difference between my mother's voice and other people's voices. 7, it is difficult to concentrate, can't be quiet for a minute or two. 8, born 1 ~ 2 months, still can't look into the eyes of adults, don't laugh when teasing, and can't actively track relatives and colorful things with their eyes. It's so quiet, it seems that there is no him in the room.