Young language learners often display a U-shaped developmental pattern in which they use terms correctly early in development, go through a period in which they make a lot of mistakes, and then use terms correctly again

Cite one area of language in which we see U-shaped development. Explain how children's performance changes as they gain more experience with that area of language (provide specific examples when appropriate).

What will be an ideal response?

One example of a U-shaped function is the development of children's ability to form the past tense. When children first learn the past tense, they learn each separate case, so they are likely to use the correct form. They may say, "I went to the park." However, after they have learned a large number of verbs, they abstract the typical past tense pattern of putting "ed" at the end. During this period, they are likely to overgeneralize the pattern. They may say, "I goed to the park." As their experience with verbs increases even more, they eventually go back to the correct form. A second example of a U-shaped function is the development of children's ability to use the prefix "un." When children first learn words with the prefix "un," they merely repeat words that they have heard adults say, so they are likely to use it correctly. They may say, "He unlocked the door." Later, they may start using "un" incorrectly. They may say, "I don't like that picture. I want you to undraw it." Eventually, they figure out that "un" can only be used as a prefix in specific situations, so they start using it correctly again.