Final answer:
Children's language and cognitive milestones vary by age, with developments in vocabulary, understanding of commands, physical coordination, and problem-solving skills notable from six months to five years of age.
Step-by-step explanation:
The developmental stages of language and cognitive growth are essential cognitive milestones for children at various ages. One-year-old toddlers generally can use short one- or two-syllable words, such as "ball" or "mama," and are beginning to understand several more, along with simple commands. By the age of two years, they can use up to 50 words and understand significantly more, showing abilities such as obeying simple verbal instructions and demonstrating some self-awareness and independence.
Six-month-old infants engage in vocal play and start making syllable sounds like "mama" or "dada." They experience stranger anxiety and show physical development milestones like pulling themselves into a seated position. At ten months, infants can crawl, sit unsupported, look for dropped objects, and begin to babble.
Three-year-old toddlers speak in short sentences, ask questions, sing along with simple songs, and engage in role-playing activities, while five-year-old children boast a vocabulary of at least 1,500 words, can count past 20, and show readiness for more complex humor and learning concepts like time and monetary value.