The precursors of autism are mainly manifested in the following ways: First, if the child is found to have a delayed language development and low intelligence, which means that he or she is already very old and still cannot speak, or can only say a few simple words. At the same time, the IQ is very low compared to children of the same age, and significantly behind children of the same age, it is possible that the problem is autism. Children with autism may have a lack of interest and may not be interested in the toys and games that children generally enjoy. The toys they like may not be things that children would normally like or identify as toys, such as tires, electric fans, switches, knobs, etc. Some of the most prominent signs of autism are that these children are reluctant to interact with others, and are particularly passive and reluctant to interact with others at school, at home, and with children their own age. Every day, the child behaves in a particularly selfish and withdrawn manner, does not play with other children, and has no desire to interact with others.