One very important thing you can do for your child's speech and language development is to READ. Read to your child. Read with your child. Have your child read or even pretend to read. Don't be afraid to read the same books over and over again. When you read predictable, age-appropriate books to a child, you provide the opportunity to hear the sounds and structure of language over and over which is how children learn best. Having the child name objects, recall the story or read aloud to you can strengthen the child's ability to organize thoughts into words, sentences, and groups of sentences. Reading aloud to young children is one of the best activities to stimulate language and cognitive skills; it also builds motivation, curiosity and memory. (Bardige, B. Talk to Me, Baby! (2009), Paul H. Brookes Pub Co.)
For tips on reading to your child:
http://reachoutandread.org/why-we-work/importance-of-reading-aloud
http://readingrockets.org/article/reading-together-tips-parents-children-speech-and-language-problems
http://www.rif.org/us/literacy-resources/articles/reading-with-your-child.htm