diff --git a/05-Linear-Regression/08-Linear-Regression-in-scikit-learn/08-Linear-Regression-in-scikit-learn.ipynb b/05-Linear-Regression/08-Our-Linear-Regression/08-Our-Linear-Regression.ipynb
similarity index 99%
rename from 05-Linear-Regression/08-Linear-Regression-in-scikit-learn/08-Linear-Regression-in-scikit-learn.ipynb
rename to 05-Linear-Regression/08-Our-Linear-Regression/08-Our-Linear-Regression.ipynb
index abb4de3..a67b6ec 100644
--- a/05-Linear-Regression/08-Linear-Regression-in-scikit-learn/08-Linear-Regression-in-scikit-learn.ipynb
+++ b/05-Linear-Regression/08-Our-Linear-Regression/08-Our-Linear-Regression.ipynb
@@ -4,7 +4,7 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "## 08 scikit-learn 中的 Linear Regression"
+    "## 08 实现我们自己的 Linear Regression"
    ]
   },
   {
diff --git a/05-Linear-Regression/08-Linear-Regression-in-scikit-learn/playML/LinearRegression.py b/05-Linear-Regression/08-Our-Linear-Regression/playML/LinearRegression.py
similarity index 100%
rename from 05-Linear-Regression/08-Linear-Regression-in-scikit-learn/playML/LinearRegression.py
rename to 05-Linear-Regression/08-Our-Linear-Regression/playML/LinearRegression.py
diff --git a/05-Linear-Regression/08-Linear-Regression-in-scikit-learn/playML/SimpleLinearRegression.py b/05-Linear-Regression/08-Our-Linear-Regression/playML/SimpleLinearRegression.py
similarity index 100%
rename from 05-Linear-Regression/08-Linear-Regression-in-scikit-learn/playML/SimpleLinearRegression.py
rename to 05-Linear-Regression/08-Our-Linear-Regression/playML/SimpleLinearRegression.py
diff --git a/05-Linear-Regression/08-Linear-Regression-in-scikit-learn/playML/__init__.py b/05-Linear-Regression/08-Our-Linear-Regression/playML/__init__.py
similarity index 100%
rename from 05-Linear-Regression/08-Linear-Regression-in-scikit-learn/playML/__init__.py
rename to 05-Linear-Regression/08-Our-Linear-Regression/playML/__init__.py
diff --git a/05-Linear-Regression/08-Linear-Regression-in-scikit-learn/playML/kNN.py b/05-Linear-Regression/08-Our-Linear-Regression/playML/kNN.py
similarity index 100%
rename from 05-Linear-Regression/08-Linear-Regression-in-scikit-learn/playML/kNN.py
rename to 05-Linear-Regression/08-Our-Linear-Regression/playML/kNN.py
diff --git a/05-Linear-Regression/08-Linear-Regression-in-scikit-learn/playML/metrics.py b/05-Linear-Regression/08-Our-Linear-Regression/playML/metrics.py
similarity index 100%
rename from 05-Linear-Regression/08-Linear-Regression-in-scikit-learn/playML/metrics.py
rename to 05-Linear-Regression/08-Our-Linear-Regression/playML/metrics.py
diff --git a/05-Linear-Regression/08-Linear-Regression-in-scikit-learn/playML/model_selection.py b/05-Linear-Regression/08-Our-Linear-Regression/playML/model_selection.py
similarity index 100%
rename from 05-Linear-Regression/08-Linear-Regression-in-scikit-learn/playML/model_selection.py
rename to 05-Linear-Regression/08-Our-Linear-Regression/playML/model_selection.py
diff --git a/05-Linear-Regression/08-Linear-Regression-in-scikit-learn/playML/preprocessing.py b/05-Linear-Regression/08-Our-Linear-Regression/playML/preprocessing.py
similarity index 100%
rename from 05-Linear-Regression/08-Linear-Regression-in-scikit-learn/playML/preprocessing.py
rename to 05-Linear-Regression/08-Our-Linear-Regression/playML/preprocessing.py
diff --git a/05-Linear-Regression/09-kNN-Regressor/09-kNN-Regressor.ipynb b/05-Linear-Regression/09-Regression-in-scikit-learn/09-Regression-in-scikit-learn.ipynb
similarity index 88%
rename from 05-Linear-Regression/09-kNN-Regressor/09-kNN-Regressor.ipynb
rename to 05-Linear-Regression/09-Regression-in-scikit-learn/09-Regression-in-scikit-learn.ipynb
index ed27f94..b98b2e8 100644
--- a/05-Linear-Regression/09-kNN-Regressor/09-kNN-Regressor.ipynb
+++ b/05-Linear-Regression/09-Regression-in-scikit-learn/09-Regression-in-scikit-learn.ipynb
@@ -4,7 +4,7 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "## 09 kNN Regressor 解决回归问题"
+    "## 09 scikit-learn中的回归问题"
    ]
   },
   {
@@ -70,9 +70,16 @@
     "X_train, X_test, y_train, y_test = train_test_split(X, y, random_state=666)"
    ]
   },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "### scikit-learn中的线性回归"
+   ]
+  },
   {
    "cell_type": "code",
-   "execution_count": 9,
+   "execution_count": 5,
    "metadata": {},
    "outputs": [
     {
@@ -81,7 +88,7 @@
        "LinearRegression(copy_X=True, fit_intercept=True, n_jobs=1, normalize=False)"
       ]
      },
-     "execution_count": 9,
+     "execution_count": 5,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -95,7 +102,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 10,
+   "execution_count": 6,
    "metadata": {},
    "outputs": [
     {
@@ -108,7 +115,7 @@
        "        -3.99667727e-01])"
       ]
      },
-     "execution_count": 10,
+     "execution_count": 6,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -119,7 +126,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 11,
+   "execution_count": 7,
    "metadata": {},
    "outputs": [
     {
@@ -128,7 +135,7 @@
        "32.645660839653587"
       ]
      },
-     "execution_count": 11,
+     "execution_count": 7,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -139,7 +146,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 12,
+   "execution_count": 8,
    "metadata": {},
    "outputs": [
     {
@@ -148,7 +155,7 @@
        "0.80089161995191116"
       ]
      },
-     "execution_count": 12,
+     "execution_count": 8,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -166,16 +173,16 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 13,
+   "execution_count": 10,
    "metadata": {},
    "outputs": [
     {
      "data": {
       "text/plain": [
-       "0.6319037967897394"
+       "0.60267450508095299"
       ]
      },
-     "execution_count": 13,
+     "execution_count": 10,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -183,14 +190,14 @@
    "source": [
     "from sklearn.neighbors import KNeighborsRegressor\n",
     "\n",
-    "knn_reg = KNeighborsRegressor(n_neighbors=3)\n",
+    "knn_reg = KNeighborsRegressor()\n",
     "knn_reg.fit(X_train, y_train)\n",
     "knn_reg.score(X_test, y_test)"
    ]
   },
   {
    "cell_type": "code",
-   "execution_count": 15,
+   "execution_count": 11,
    "metadata": {},
    "outputs": [
     {
@@ -204,7 +211,7 @@
      "name": "stderr",
      "output_type": "stream",
      "text": [
-      "[Parallel(n_jobs=-1)]: Done 180 out of 180 | elapsed:    1.1s finished\n"
+      "[Parallel(n_jobs=-1)]: Done 180 out of 180 | elapsed:    1.3s finished\n"
      ]
     },
     {
@@ -220,7 +227,7 @@
        "       scoring=None, verbose=1)"
       ]
      },
-     "execution_count": 15,
+     "execution_count": 11,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -247,7 +254,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 17,
+   "execution_count": 12,
    "metadata": {},
    "outputs": [
     {
@@ -256,7 +263,7 @@
        "{'n_neighbors': 3, 'p': 1, 'weights': 'uniform'}"
       ]
      },
-     "execution_count": 17,
+     "execution_count": 12,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -267,7 +274,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 18,
+   "execution_count": 14,
    "metadata": {},
    "outputs": [
     {
@@ -276,7 +283,7 @@
        "0.57325417167989967"
       ]
      },
-     "execution_count": 18,
+     "execution_count": 14,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -284,6 +291,26 @@
    "source": [
     "grid_search.best_score_"
    ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 15,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "0.73394216830389403"
+      ]
+     },
+     "execution_count": 15,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "grid_search.best_estimator_.score(X_test, y_test)"
+   ]
   }
  ],
  "metadata": {
diff --git a/05-Linear-Regression/Chapter-05.key b/05-Linear-Regression/Chapter-05.key
index 4d31561..35b26f0 100644
Binary files a/05-Linear-Regression/Chapter-05.key and b/05-Linear-Regression/Chapter-05.key differ