The present simple is a fundamental tense in modern English used to express habitual actions, general truths, and scheduled future events. It is formed differently for third-person singular subjects and has specific rules for negative and interrogative forms.
• The present simple is used for habits, unchanging states, and certain future events.
• Its affirmative form is simply subject + base verb, except for third-person singular.
• Negative forms use the auxiliary 'do/does' with 'not' before the base verb.
• Interrogative forms invert the auxiliary 'do/does' with the subject.
• Frequency adverbs are commonly used with the present simple to indicate how often actions occur.