Gerunds are Nouns
Form: VERB+ing
Negative: not VERB+ing
Examples:
Reading good literature increases your vocabulary. (subject)
His favorite thing to do is reading comic books. (complement)
She loves reading romance novels. (object)
He was arrested for robbing the local jewelry store. (object of preposition)
The trek will last a week and involves hiking over twenty miles through mountains and forests. (object)
I understand buying an SUV if you have a large family to haul, but it doesn't make much sense, otherwise. (object)
Sara enjoys not working. (object)
 
A possessive pronoun can come before a gerund:
I hope that you appreciate his offering you this opportunity.