Communication is complex, however development does usually follow a typical pattern.
Speech and Language Therapists (SLTs) consider a number of aspects of development, often referred to as the Pyramid of Communication. Each skill can only develop if the skills underneath it have been firmly established.
For example, a child needs to develop their attention and listening before they will be able to fully engage in play. Their understanding then develops through play. When understanding is developed, a child will be able to learn how to express themselves. Finally clear speech develops.