In Norwegian grammar, distinguishing between the present tense and past tense of verbs is crucial for clear and accurate communication. The present tense in Norwegian is formed by adding -r, -er, or -s to the base form of the verb, depending on the verb group it belongs to. The past tense, however, takes different endings based on the same grouping, such as -et, -de, or -te. Understanding the difference between the two tenses allows for a correct expression of when actions are taking place.