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Ghost.ipynb

@@ -261,14 +261,14 @@
     "# Who Wins?\n",
     "\n",
     "Who wins a game if both players play rationally?  To answer that, consider the general situation at some point\n",
-    "suring the game where\n",
+    "during the game where\n",
     "a player is presented with a fragment. That player can win if either:\n",
     "- The fragment is a word (meaning the other player formed the word, and lost).\n",
     "- The fragment is not a legal fragment (meaning the other player made a mistake, and lost).\n",
-    "- At least one of the legal plays puts the opponent in a position from which they *cannot* win.\n",
+    "- At least one of the legal plays  in this position puts the opponent in a position from which they *cannot* win.\n",
     "\n",
-    "The function `win(vocab, fragment)` implements this idea. It returns a winning fragment if there is one, otherwise `None`. In particular, it returns `fragment` if the current player has already won because `fragment` forms\n",
-    "a word or illegal fragment, and it returns one of the legal plays if the play leads to a position from\n",
+    "The function `win(vocab, fragment)` implements this. It returns a winning fragment if there is one, otherwise `False`. In particular, it returns `fragment` if the current player has already won (because `fragment` is\n",
+    "a word or illegal fragment), and it returns one of the legal plays if the play leads to a position from\n",
     "which the opponent *cannot* `win`."
    ]
   },
@@ -282,7 +282,7 @@
    "source": [
     "def win(vocab, fragment=''):\n",
     "    \"\"\"Does the current player have a forced win? \n",
-    "    Return fragment if the player has already won, or return a play that forces a win.\"\"\"\n",
+    "    If so, return a play (or the current fragment) that leads to a win.\"\"\"\n",
     "    if fragment in vocab.words or fragment not in vocab.fragments:\n",
     "        return fragment\n",
     "    for play in vocab.legal_plays(fragment):\n",