diff --git a/06-matplotlib/06.04-working-with-text---math-expression.ipynb b/06-matplotlib/06.04-working-with-text---math-expression.ipynb
index a36032f6..e968e039 100644
--- a/06-matplotlib/06.04-working-with-text---math-expression.ipynb
+++ b/06-matplotlib/06.04-working-with-text---math-expression.ipynb
@@ -208,7 +208,7 @@
     "`\\grave a`| $\\grave a$\n",
     "`\\hat a`| $\\hat a$\n",
     "`\\tilde a` | $\\tilde a$\n",
-    "`\\4vec a` | $\\vec a$\n",
+    "`\\vec a` | $\\vec a$\n",
     "`\\overline{abc}`|$\\overline{abc}$\n",
     "`\\widehat{xyz}`|$\\widehat{xyz}$\n",
     "`\\widetilde{xyz}`|$\\widetilde{xyz}$"
diff --git a/06-matplotlib/06.09-do-not-trust-the-defaults.ipynb b/06-matplotlib/06.09-do-not-trust-the-defaults.ipynb
index 2e050f92..8d2b1835 100644
--- a/06-matplotlib/06.09-do-not-trust-the-defaults.ipynb
+++ b/06-matplotlib/06.09-do-not-trust-the-defaults.ipynb
@@ -571,7 +571,7 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "我们可以使用 `anotate` 函数来注释特殊的点，假设我们要显示的点是 $2\\pi/3$："
+    "我们可以使用 `annotate` 函数来注释特殊的点，假设我们要显示的点是 $2\\pi/3$："
    ]
   },
   {
diff --git a/README.md b/README.md
index 3f647fe2..b4e87c1f 100644
--- a/README.md
+++ b/README.md
@@ -19,6 +19,10 @@ https://item.jd.com/12328920.html
 
 天猫、亚马逊、当当均有销售。
 
+**打赏一下意思意思？**
+
+![](payment.jpeg)
+
 ---
 
 ## 简介
diff --git a/index.md b/index.md
index 53945a03..14a45561 100644
--- a/index.md
+++ b/index.md
@@ -150,8 +150,4 @@
 - [12. **Pandas**](12-pandas)
 	 - [12.01 十分钟上手 Pandas](12-pandas/12.01-ten-minutes-to-pandas.ipynb)
 	 - [12.02 一维数据结构：Series](12-pandas/12.02-series-in-pandas.ipynb)
-	 - [12.03 二维数据结构：DataFrame](12-pandas/12.03-dataframe-in-pandas.ipynb)
-     
-**打赏一下意思意思？**
-
-![](payment.jpeg)
\ No newline at end of file
+	 - [12.03 二维数据结构：DataFrame](12-pandas/12.03-dataframe-in-pandas.ipynb)
\ No newline at end of file
diff --git a/payment.jpeg b/payment.jpeg
new file mode 100644
index 00000000..7dc37b8d
Binary files /dev/null and b/payment.jpeg differ