The 4-year-old baby’s speech is still not clear, indicating that the child’s language development is backward, this we need to actively look for the cause. First of all, we need to check the child’s intelligence and hearing, if the child’s intelligence has problems, there will certainly be different degrees of language development backward, if there are problems with the hearing, the speech is certainly not clear, if there is no problem in both aspects. If there is no problem in both aspects, then we need to check whether the child has problems in sound formation, for example, is there a problem of short tongue tie? Or is there a hidden cleft palate? If these two causes do exist, then the child needs to go to the relevant department for surgical treatment. In addition, some children’s unclear speech may be related to psychological factors, the child is not willing to communicate with others, or some children with autism and other mental illnesses, may also be behind in language development, which requires the parents and teachers to actively guide the child, usually to communicate with the child more, do parent-child reading, tell the child more stories, so that the child can listen to more practice, to cultivate the child’s ability to express his or her language, and also let the child try to sing, which is good for language development. You can also let your child try singing, which is also helpful for language development. If the child has autism, it is necessary to take the child to a specialized hospital for mental diseases. To summarize, if a 4-year-old child’s speech is not clear, as parents, we should pay attention to the child’s usual speech and behavior, observe whether the child’s unclear speech is related to hearing, intelligence, phonological and mental illnesses, and then take active treatment measures after clarifying the cause.