A descriptive grammar is a set of rules about language based on how it is actually used. In a descriptive grammar there is no right or wrong language. It can be compared with a prescriptive grammar, which is a set of rules based on how people think language should be used.
A descriptive grammar might include ‘He goes...', meaning ‘He said'.
In the classroom
Learners can be encouraged to move away from a prescriptive approach to grammar by using a guided discovery, or inductive, approach, in which they look for examples of variations in use in authentic texts. These examples can be compared to prescriptive rules in order to decide if they are useful or not.