The contrast – a story about two professors

I was making an effort to catch the essence of what she was illustrating. The chart showed how Old English changed and developed into Middle English. How the words in late Old English period started loosing their inflections. A slight noise was intruding. What was it? I looked out the window. The sun was shining brightly. The leaves of birch trees showed a deep tone of green. It was unusually quiet, even the birds were taking a rest on this early spring day in April.