Now my turn comes to be forgetful. This morning no sooner had I closed the door than I remember my key was inside. Things like this happen more often than before. What a poor memory! 

On second thought, I believe it's reasonable. It is rather the mind and attention than the age that speaks for such absent-mindedness specific to elders. I rarely forget my camera in outdoors, less for my cell phone used for mobile pay or a Meituan shared-bike. For a bus ride, I always have my bus-card with me. In hot days I never forget to bring a water bottle. Let alone a face mask now. But not the keys (unless I put them inside my wallet).  Outdoors, we may carry a number of small things for possible use, the useless among them, to me at least, is the home key - not one to carry but a handful of ones in various shapes and sizes. 

In my mind, man, weaker in energy and mind with passing days, has no choice but to single out and tackle the principal contradictions in present day complex way of living. And that’s the key to the life of elder people.