This document summarizes the rules for using the present simple tense in grammar. It outlines that the present simple is used to talk about habits, permanent situations, and general truths. It provides examples of affirmative, negative, and interrogative sentence structures in the present simple. It also describes the different verb conjugations in the third person singular including adding -s, -es, and changing the final letter. Adverbs of frequency are described as expressing how often an action occurs, and examples are given of their placement in sentences.