This game may be annoying to some parents, but it is a game thoroughly enjoyed by many infants this age. Many children are also learning to follow simple instructions, and they may anticipate a reward for the successful completion of an act or a command. By nine months of age, most babies have begun vocalizing to toys, people, and animals in sentence-like syllables. Many children this age seem to listen carefully to the conversations of other people. They may also imitate sounds they hear in these conversations.
Most babies say their first words between ten and eleven months of age.
Most of what is said is still gibberish, but sounds will be increasingly more intelligible as children approach eleven to twelve months.