Some parents want to know whether their baby is smart, and they can take the following aspects as reference standards. First of all, can the baby do big sports, such as sitting alone, sitting up straight, or returning to the seat after getting the object. Secondly, whether there are fine movements to get the objects on the table. If there are two toys, the baby can take one toy and then the other. The third is adaptability, whether the toy can change hands, or whether it can reach the toy in the distance.