The gerund is a 'verbal noun'such as 'amandi' in 'ars amandi'. It is translated by giving the verb the ending '-ing' (e.g. the art of loving). This can lead to confusion with the present active participle which has a similar translation (e.g. 'puer amans': the loving boy). The gerund follows the 2nd declension neuter, like scutum, and its function depends on its case e.g. the preposition 'AD' followed by a gerund in the accusative denotes purpose. It is not to be confused with the gerundive.