Language is a system of symbols and rules that is used for meaningful communication. A system of communication has to meet certain criteria in order to be considered a language: 1  A language uses symbols, which are sounds, gestures, or written characters that represent objects, actions, events, and ideas. A language uses symbols, which are sounds, gestures, or written characters that represent objects, actions, events, and ideas. 2  Symbols enable people to refer to objects that are in another place or events that occurred at a different time.
Also remember that children between the ages of 6 and 18 months can normally move up or down on their percentiles, but older children should follow their growth curve fairly closely. Answers to examples: 1) 50th percentile, 2) 10th percentile, 3) 50th percentile, 4) 75th percentile, 5) about the 15th percentile.
A percentile is a number between 0 and 100 that shows how you rank compared to other students. It represents the percentage of students in a particular grade whose scores fall at or below your score. For example, a 10th-grade student whose Math percentile is 57 scored higher or equal to 57 percent of 10th-graders.