1. Overview:
The present simple is used to talk about habits, routines, and facts. "Do" and "does" are used to make questions and negative sentences. "To be" (am/is/are) is used to describe people, places, or things.
2. Cases of Usage "do/does":
Case 1: Using "do" for questions in the present simple.
Example: Do you like pizza?
Case 2: Using "does" for questions in the present simple with he, she, or it.
Example: Does she play soccer?
Case 3: Using "do" for negative sentences with I, you, we, or they.
Example: I do not (don't) like broccoli.
Case 4: Using "does" for negative sentences with he, she, or it.
Example: He does not (doesn't) watch TV.
3. Cases of Usage "to be":
Case 1: Using "to be" for statements about identity or state.
Example: I am a student.
Case 2: Using "to be" for questions about identity or state.
Example: Are you happy?
Case 3: Using "to be" for negative sentences.
Example: She is not (isn't) a teacher.
