What ending does a present participle have?

A present participle is formed by adding "ing" to the base form of a verb. This form is used to indicate an ongoing action or to create continuous tenses, such as "running," "swimming," or "eating." Present participles can also function as adjectives, as in "the running water." The other endings, such as "ed," "s," and "en," correspond to different grammatical aspects. For example, "ed" is used for past participles, "s" is typically used for third-person singular present tense verbs, and "en" forms can indicate the past participle of some verbs but do not apply to present participles. Therefore, the correct ending for a present participle is indeed "ing."