You orYour Before Gerunds
Gerunds are verb forms serving as nouns. They end in -ing: baking, being, eating, chewing, talking. To highlight the gerund (i.e., the activity), use a possessive noun or a possessive pronoun before it.
• The teacher objected to their eating all the icing.
[NOT: The teacher objected to them eating all the icing.] It isn't the fact that they are the ones who ate all the icing; it's the activity that she objected to.
• Your [NOT: You] eating all the icing was not nice.
• Your [NOT: You] being here was appreciated.
• We appreciate your [NOT: you] being here.
• We appreciate Jane's [NOT: Jane] being here.