1. Language ability develops slowly, and people can't speak as fluently as their peers.

2. The development of motor skills is slow, such as not being able to climb or walk.

3. inattention, easy to get distracted or forget what you are doing.

4. Poor memory, unable to remember simple things or instructions.

5. Emotional instability, excitability or anxiety.

6. Slow response to the surrounding environment, unable to understand or adapt to new things.

7. Poor social skills and lack of interest or ability to interact with others.

If parents find that their children have the above symptoms, they should consult a doctor for evaluation and treatment in time.