Three Old Ladies Were Sitting At The Dinner Table

Three old ladies were sitting at the dinner table discussing their problems with getting old.
The first one said,
“Sometimes I catch myself with a jar of mayonnaise in my hand while standing in front of the refrigerator, and I can’t remember whether I need to put it away, or start making a sandwich”.
The second lady says,
“Yes, sometimes I find myself on the landing of the stairs and can’t remember whether I was on my way up or on my way down”.
The third one says,
“Well, ladies, I’m glad I don’t have any of those problems, knock on wood”.
As she hit her knuckles on the table she looked up and said,
“That must be the door… I’ll get it!”