A participle is something between a verb, an adjective and a noun. At its base, it is a verb. In its form, it is a noun. And its function is most similar to that of an adjective. That all sounds pretty complicated, but is easy to learn for English speakers since we use participles all the time.
Take, for example, the word “eating.” This, along with most -ing words in English, is a participle. Note that this participle comes from the verb “to eat.” It can be used in several different ways. It can be used together with “is” to express continuous action, like in the sentence, “He is eating the sandwich.” But it also can function like a normal adjective, as in, “Want to join our eating contest?” Finally, this participle can also act like a noun (i.e. a substantival adjective)—“I love eating!” Hebrew uses participles in much the same way.