When learning a language, as a child or adult, understanding what is being said is the first step to learning a new language. Speaking fluently occurs next.
Babies and toddlers listening skills are much more developed than their speaking vocabulary
This means you can read books that exceed your child’s ability to speak. I read simple chapter books to my children when they were 4 or 5 years old.

Encourage oral language by having your child tell you about their drawing, their toys, favorite food and anything else that interests them.
If you have a video camera, let them perform and speak before the camera.