The gerund is formed in a similar way to the present participle. In most cases this involves taking the nous form of the verb and then dropping the -ons ending and replacing it with -ant. This forms the present participle and then to form the gerund the preposition 'en' is used at the start. There are some irregular verbs that need learning separately as they do not follow this rule such as avoir and etre which have the gerund forms of en ayant and en etant respectively. The gerund is primarily used to introduce an action which is being performed whilst also performing another or as a result of another. For example: 'Je fais mes devoirs en mangeant une banane' can be translated as 'I do my homework while eating a banana'. Here the gerund is used to indicate that two actions are hapening simultaneously. Another example: 'J'ai reussi mes examens en faisant mes devoirs tout le temps' can be translated as 'I passed my exams by doing my homework all the time'. In this example the gerund is used to indicate the fact that one action was performed by doing another.