Your kiddo's language development is happening in full swing, however, at this stage, there's one thing that can help your kid have faster and more effective development of language skills. It's simple! It is important to give your child the opportunity to make friends of all age groups.
Do not be alarmed if your child comes back with some words that are not allowed to be used because you can always correct them. Only if your young child behaves and says something inappropriate can you guide them in the right path. Forcing them to interact with children of their age group only will greatly hamper their language and vocabulary.
What you need to know
Language development happens much better in mixed age groups where older children act as role models for younger children with limited language skills. If your child is surrounded with children of various ages, they get to interact at various levels of complexity. The language skills develop more rapidly than when interacting only with peers of their age group. Older children form more complex and longer sentences. As your child looks up to the older friends as role models, they would also like to imitate them in speaking as well, and thus learn faster.
Older children can guide and help your younger child in a new setting. In the process both develop self-esteem and self-confidence. You will soon see your 4 year old acting as a guide to a child even younger.