Children’s language development often begins with easy speech and progresses to more difficult speech. Most studies point to the early development of bilabial sounds and the early onset of lingual apical and lingual root sounds compared to both labiodental and lingual front sounds. In general, most speech sounds should be developed by about age five. Children often have special phonological patterns in their speech development, such as frontal phonemes, and say “Ah Gong” as “Ah Dong”. Another type is the substitution of air sounds by non-air sounds, such as saying “tummy” for “free son”. If these cases occur in the early developmental stages of children, parents should not be overly concerned yet, as most children will gradually develop correct language later on. Language development during infancy (0-3 years) Speech during this period can be divided into two stages: (1) Pre-linguistic speech: the infant’s crying and laughing, attention to sounds, babbling and yapping, etc. These do not sound like real speech, so they are called pre-linguistic speech. (2) Linguistic speech: Starting with simple single words, they slowly build up single words and vocabulary, and then form short sentences. Children usually begin to speak at 10 to 14 months of age, and the content is mostly related to everyday needs or experiences. Language development in preschoolers (3-6 years) Words and sentences are more abundant, words are spoken fluently, and errors in approach are reduced. Storytelling skills also characterize language development during this period, moving from describing events in fragments to gradually being able to tell stories with clear themes and complete structures. In addition, children also use language to meet social needs. Language Development in School-Aged Children (6-12 years) As children begin elementary school, they are exposed to more people and things and have much more opportunity to communicate. Children develop an understanding of their own communication skills and become aware from experience that they are good or bad at language. If children feel that they are not speaking well or are often frustrated with their speech, they may adopt ways to cope.