It is important to understand that not all children will follow the exact sequence in their language and communication development. The following information about developmental milestones in this area is important to note, however, so that you are aware of the typical skills mastered at various ages from four months to 10-11 years of age.
Pre-linguistic Stage: 4 to 12 months
During this early stage, babies begin to communicate with care providers. They recognize different tones of voices and coo and gurgle to show happiness. They smile in response to other people's faces and cry to show hunger, to express being tired, or signal when in distress. At six months, their babbles have short sounds like "da da" and "ma ma" and become more aware of emotions in others' voices. They begin to enjoy rhymes with simple actions and music. At nine months, they can recognize their own names, imitate simple words, and understand words of one syllable like "bye, bye." When they point, they often use the first letter sound of what is being pointed to. Their babbling begins to take on the intonation of speech.
At age 12 months, they have a great deal of understanding as to what is being said to them (e.g., "come here," "clap your hands," "go nightie," "no, stop!"), and they, in turn, are communicating their needs and wants by gesturing. Vowels and consonants are put together in repetitive sounds and the 12-month-old child enjoys simple games (e.g., pat-a-cake or peek-a-boo).
Linguistic Stage: 15 months to 8 years
From 12-15 months of age, children develop and use their own words for a given object or person. They use what is called "holophrases," a single word to represent several meanings by using gestures and changing the sound of the word. Eventually they put words together to form short sentences.
At 15 months, children can understand about 10 words and can point to express themselves and say a single word to convey their thoughts.
At age 18 months, they put two words together in "telegraphic speech," a term used for putting important words together in a grammatically correct manner (e.g., "daddy come," "bye mommy"). Their vocabulary increases monthly with an average of 10-30 words. They can repeat words and sentences and use language to point out objects and name belongings.
At age 2, they are learning words more quickly and use the plural "s" correctly for simple objects (e.g., dolls, dogs), but they may make incorrect plurals, as well (e.g., fishes). Two-year-old children may have trouble with past tense (e.g., ranned). They start to use negatives (e.g., there no toys). Sentence length increases. Questions of "what" and "why" are common.
At age 3, strangers can understand what is being said and sentences are now about 4-5 words long with the correct use of pronouns. Children at this age enjoy asking questions, talk to themselves during free play, and know some basic nursery rhymes.
At age 4, their vocabulary is more extensive and they use longer and more complex sentences. They can tell stories with the correct sequence of events. Their language use extends to describing how others feel, questioning, and everyday application to share, take turns, to disagree, and to collaborate. The speech patterns are developed with few incorrect uses.
At age 5, vocabulary includes readiness skills of shapes, colors and numbers. Their sentences may include incorrect grammar and the pronunciation may still be childish. They ask more precise questions and are able to offer opinions.
At age 6, they use all of the pronouns correctly and can understand opposites and about 13,000 words. They can classify objects according to color, shape, and use and use these words to categorize.
At age 7, their understanding of words doubles to 26,000, and along with this, they understand time intervals and seasons of the year. They are aware of mistakes in others' speech.
At age 8, they can carry on meaningful conversations with adults and follow two- and three-step directions without repetition. Their sentences contain compound and complex subjects and predicates with little grammar errors. They are able to read age-level text and are emergent writers, as well. They have learned some social interactions and use them appropriately: "please," "thank you," and "you're welcome."
After age 8, children develop higher level speech and language skills, using words to predict/draw conclusions, to understand and express points of view, to understand comparative words, to give reasons and explanations, to begin conversations with other children and adults they may not know, and to understand/use passive sentences (e.g., "The boy was given money by the banker.")
As the years progress from age 9 to 11-12, the acquired speech and language skills are refined. The children can listen longer to a variety of speakers and understand more complex information. Their expressive language skills sharpen as they can now persuade by presenting convincing arguments and enjoy interviewing others. Their speech is fluent with the appropriate pitch, volume, and pause for emphasis. All of the speech sounds should be formed at this time and there should not be any articulation errors. They can distinguish from fact and opinion and know colloquial speech. The child of this age can negotiate in situations of conflict and know how word choice changes when interacting with different people (e.g., the teacher vs the friend vs Grandmother vs the younger sibling).