According to the National Institute on Deafness and Other Communication Disorders, or NIDCD, there is a natural progression in language development, from simple skills to complex skills. Experts have identified these skills and the age at which most children develop them, creating a timeline of language milestones starting when a baby is 3 months old, many months before your baby will utter his first word.
Birth to 1 Year
According to the American Speech-Language-Hearing Association, or ASHA, by 3 months of age a baby is making pleasure sounds, such as cooing or laughing as well as fussing and crying. By 6 months she is babbling, repeating syllables using "p," "b" and "m" sounds, such as "ba, ba, ba." By 1 year she is making longer babbling sounds as she groups them together. She also uses speech or sounds to get attention, uses gestures to communicate and says one or two short words, such as "mama" or "dada."
By 2 Years
A child in his first year is saying more words every month. He starts to form questions and sentences using one or two words, like "Mommy up." According to NIDCD, approaching his second year he starts trying to imitate simple words, understands simple verbs, such as "eat" and begins to use pronouns, such as "mine." He will be able to name objects around the home and have a vocabulary of 150 to 300 words.
By 3 Years
According to ASHA, a child in her second year is using two or three word sentences and is easier to understand. She is using more sounds, such as "k," "g," "f," "t," "d" and "n." She can answer simple questions, use pronouns such as "you" and "I" and use inflection when asking questions. By 3 years of age she has a vocabulary of about 900 to 1,000 words.
By 4 Years
By 4 years of age a child is able to talk about activities they did during the day, mostly using sentences that have four words or more. He is using more sounds, but is still having trouble with the difficult ones such as "sh," "ch," "th," "v" and "z." Strangers are able to understand him most of the time and he uses "ing" at the end of verbs.
By 5 Years
A child's language is developed enough by age 5 that she can tell stories, say rhyming words, is almost completely understandable except when using long difficult words and says about 200 to 300 different words. She will usually use correct grammar and fairly complex sentences and will know some irregular past tense verbs, such as saying "ran" instead of the incorrect "runned."
