The next stage is the telegraphic phase. In this stage infants can form short sentences (i.e., Daddy sit, or Mommy drink). This typically occurs between the ages of one and a half and two and a half years old. This stage is particularly noteworthy because of the explosive growth of their lexicon. During this stage, infants must select and match stored representations of words to the specific perceptual target word in order to convey meaning or concepts. With enough vocabulary, infants begin to extract sound patterns, and they learn to break down words into phonological segments, increasing further the number of words they can learn. At this point in an infant's development of speech their lexicon consists of 200 words or more and they are able to understand even more than they can speak.