There are five commas in the paragraph below. Two are placed correctly though, three are not. Re-write the paragraph indicating the correct and and incorrect ones.
At the age of eighty, my mother had her last bad fall, and after that her mind wandered free through time. Some days she went to weddings and funerals that had taken place half a century earlier. On others, she presided over family dinners cooked on Sunday afternoons for children who were now gray with age. Through all this, she lay in bed but moved across time, traveling among the dead decades with a speed and ease beyond the gift of physical science.