Protocols of language interactions between mothers and children are analyzed. The children ranged in age from 2.2 years to 5.0 years. Systematic changes in the interactions were found with the increasing level of language skills of the child. Mothers generally proved to be very sensitive measuring instruments of the language capacities of their children and they adapted their verbal utterances to these capacities. The syntactical forms as well as the communicated contents of the message were changed with increasing language skill. Nonhuman environmental influences on the language behaviors were studied in part and changes in the use of these situational resources by the mothers were observed. Individual differences in the teaching methods of the mothers as well as in the reactions of the children are discussed.