What benchmark corresponds with research on typical communication development in 3-year-old children?

The benchmark that corresponds with research on typical communication development in 3-year-old children is the understanding of approximately 1,000 words. By this age, children typically have a rapidly expanding vocabulary and demonstrate significant comprehension of language. Research indicates that 3-year-olds can usually understand and follow simple instructions, recognize many familiar words, and engage in basic conversations.

In contrast, using irregular third-person singular verb forms is a more advanced grammatical skill that is often not fully developed until later in childhood, around age 4 to 5. The mean length of utterance in morphemes of six is more characteristic of older preschoolers, typically around 4 to 5 years old, indicating that while a 3-year-old will have a reasonable utterance length, it may not reach that mean. Producing approximately ten consonant phonemes accurately may also be an underestimation of a 3-year-old's abilities, as many children can articulate a larger variety of sounds by this age, though intelligibility may still be developing.