diff --git a/IntroductionToNumpy/task02 索引/练习--索引，切片迭代-答案.ipynb b/IntroductionToNumpy/task02 索引/练习--索引，切片迭代-答案.ipynb
index c24795c..168bd50 100644
--- a/IntroductionToNumpy/task02 索引/练习--索引，切片迭代-答案.ipynb	
+++ b/IntroductionToNumpy/task02 索引/练习--索引，切片迭代-答案.ipynb	
@@ -4,7 +4,7 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "**交换数组arr中的列1和列2。**\n",
+    "**交换数组arr中的列1和列3。**\n",
     "\n",
     "- `arr = np.arange(9).reshape(3, 3)`\n",
     "\n",
diff --git a/IntroductionToNumpy/task02 索引/练习--索引，切片迭代.ipynb b/IntroductionToNumpy/task02 索引/练习--索引，切片迭代.ipynb
index aff3c2c..54a6b6c 100644
--- a/IntroductionToNumpy/task02 索引/练习--索引，切片迭代.ipynb	
+++ b/IntroductionToNumpy/task02 索引/练习--索引，切片迭代.ipynb	
@@ -4,7 +4,7 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "### **交换数组arr中的列1和列2。**\n",
+    "### **交换数组arr中的列1和列3。**\n",
     "\n",
     "- `arr = np.arange(9).reshape(3, 3)`\n",
     "\n",