There are two formal methods of teaching grammar:



1- The deductive approach it's a traditional style of teaching. We start logically. We present the definitions then rules then we give the examples. . In this approach, the teacher is the center of the class and responsible for the presentation and explanation of the new material.
For example, present perfect, the teacher would begin the lesson by saying, "Today we are going to learn how to use the present perfect structure". Then, He presents the rules of the present perfect structure S+HAVE OR HAS+P.P then gives the examples.

2- The inductive approach it's a modern style of teaching. The teacher introduces the rules by presenting the examples. Also encourages the students to concentrate on the examples to realize the rules.
For example, comparative form, the teacher would begin the lesson by drawing a man on the board and saying, "This is Jim. He is tall." Then, the teacher would draw another taller man next to the first one saying, "This is Bill. He is taller than Jim." The teacher would then pr***de many examples using students and real objects from the classroom, to create an understanding of the use of the structure.