Grandmother:
not in focus, and noisy, some optical errors. I would expect the focus to be on the food.

Wild flower:
While this would have been a nice picture, you need to get the blossom crisp sharp (here seen at 100%).

Swimmer:
Noise, focus, and composition. Pictures like this get accepted, if they are well in focus, nicely composed and show some value. I'm sorry, but I can't see that in this picture.
Your grandmother picture would give a pleasant series, if you would show her, correctly exposed and focussed and in different situations/settings. You will probably need to set up correct flashlight for this. Those pictures rarely work with snapshots.
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