Gerund is a non personal form, together with participle and infinitive. It can be formed two ways: simple form which would be the conjugated verb i.e leyendo (reading) and compound tense with the use of verb, ‘haber’, i.e. habiendo escuchado (having listened). The role of this form is to express in which moment, how or why there is a main action taking place.

Estar + gerundio

Estoy estudiando

I am studying

Ir + gerundio

Voy llamando

I am calling

Acabar + gerundio

Al final acabamos estudiando

We ended up studying

Llevar + gerundio

Llevo esperando una hora

I have been waiting for an hour

Quedar + gerundio

Me he quedado leyendo toda la tarde

I have been reading all afternoon

Seguir + gerundio

Él sigue llamando a la clínica

He keeps calling the clinic

Check our Conjugation section for more tense forms in Spanish.