Quick Answer
In Spanish, the verb form that ends in -ndo is called the gerundio . It is used in compound verb forms, such as Estoy nadando. (I'm swimming.), as well as adverbially, as in Salió corriendo. (literally, He left running.)
Tricky Terminology
In English the gerund is the noun form of a verb, such as swimming in the sentence Swimming is fun. (Es divertido nadar.). In Spanish, this form is translated using an infinitive verb, such as nadar.
In English, the term present participle is used to refer to verbal elements, such as swimming in I am swimming.) or -ing adjectives, such as swimming in Did you buy those swimming shorts here?.
When to Use Gerundios
In Progressive Tenses with Estar
Gerundios form the second part of progressive tenses formed with estar.
Estoy leyendo un libro.
I am reading a book.
Estaba pensando en ti.
I was thinking about you.
To Express ongoing Actions
Gerundios can be used with verbs like ir , seguir , andar and venir , to emphasize the idea of an ongoing action.
Anda buscando sus llaves.
He is walking around looking for his keys.
Vas saliendo de la enfermedad.
You are gradually coming out of your sickness.
Seguimos estudiando los libros.
We keep on studying the books.
Vengo sintiendo un gran consuelo.
I've been feeling a great comfort.
As Adverbs
Gerundios can function as adverbs, modifying the action of another verb in the same phrase.
Pasé el día leyendo.
I spent the day reading.
Chiflando y chasqueando los dedos, se bajó del autobús.
Whistling and snapping his fingers, he got off the bus.
When NOT to Use Gerundio
As Nouns
English gerunds are normally translated into Spanish as infinitives.
Me gusta hablar español.
I like speaking Spanish.
Ver es creer.
Seeing is believing.
Correr es bueno para la salud.
Running is good for your health.
As Adjectives
English adjectives that end in -ing are not translated in Spanish as gerundios.
Me compré unos zapatos de correr.
I bought myself some running shoes.
¿De quién es el bebé que llora?
Who does that crying baby belong to?
