A. The Present Tense is the base form of the verb.
B. We use the Present Simple to talk about things in general, and something happens all the time or repeatedly, or that something is true in general.
B1. something that is true in the present.
B2. something that happens again and again in the present. We use words: sometimes, often. always, and never (adverbs of frequency) with the Present Simple.
B3. something that is always true.
B4. something that is fixed in the future (permanent situations: time table etc.).
C. Questions and negatives:
C1. With the Present Simple, we use ‘do’ and ‘does’ for the third person (she/he/it) to make questions.
C2. We use ‘do’ and ‘does’ with question words like where, what and why. We use the Present Simple to say how often we do things.
C3. With the Present Simple we use ‘do’ and ‘does’ to make negatives. We use ‘does not (doesn’t)’ for the third person (she/he/it) and we use ‘do not (don’t)’ for the others.
D. Sometimes we do things by saying something: I promise ~/ I suggest ~/ I apologise ~/ I advise ~/ I insist ~/ I agree ~/ I agree ~/ I refuse ~ etc.