I had a little girl who was not speaking according to her age. What I did was to have her face me and look at my mouth when speaking in order for her to learn how to pronounce words. Her friends was also taught this strategy and would tell me when she said a word. I also used a lot of praise when she pronounced a word or made a sentence. It was difficult at first as we had to speak at a slower rate than usual when speaking to her. We eventually started speaking at a normal rate as time went along. She left for Primary School speaking.