Formation of the Gerund

The formation of the gerund is relatively simple. We take the stem to which we add the appropriate ending:
- 1st group: stem + ando (amando)
- 2nd group: stem + iendo (temiendo)
- 3rd group: stem + iendo (subiendo)

Spelling Modification

Depending on the tonic stress, completely regular gerund forms may see a spelling modification appear in order to maintain a soft sound. We speak of yod between the stem and its ending. Generally, this spelling modification appears before an e and an i which transform into a y.
- caer (to fall) => cayendo
- oír (to hear) => oyendo
- ir (to go) => yendo

Irregular Gerund

There are also completely irregular gerunds that must be known by heart. However, they can be easily remembered because a good part of these exceptions come either from the preterite (pedir) or from the diphthong (dormir). The derivatives and compounds of the verbs listed below follow the same pattern of irregularity.