The Chunk length in words is the number of lexical words used for delivering information. Theoretically speaking, the more words used in one Chunk, the more informative the Chunk should be. Based on this assumption, we explored lexical complexity of the speech content by Chunk length. In contrast to Chunk length, IPU length is the result of prosodic arrangement organized by the speakers themselves. If a speaker produces only short IPUs, the speech content is chopped into fragmentary pieces. Consequently, in addition to the fluency being affected, the content contained in each IPU accordingly becomes less informative. Our results show that the mean lengths of Chunks are 1.95, 1.82, and 2.02 for HA, CI, and NH, while for IPUs, they are 2.40, 2.36, and 2.59, respectively. Hearing children produced longer Chunks and longer IPUs than did HA and CI children. That is, regardless of whether we calculated the measure based on the text or the prosodic organization, the NH children were able to produce lexically more complex contents than were the HA and CI children, as shown in Figure 2. The NH children also tended to produce very long Chunks and IPUs, while the HA and CI children did not. In contrast, the NH children produced fewer short Chunks and IPUs than did the HA and CI children.