Respond to the following question with instances from the story and a thorough explanation.

Your question is a little broad for this space. I can give you a general comment. I think this is Serena's way of telling Offred that she knows Offred is having an affair with the commander. She implies that Offred is a "slut" like all Handmaids. We also get a sense that the commander does not have sexual relations with his wife anymore.