Update 20.md

docs/20.md

@@ -196,7 +196,7 @@ Add “caps” to the error bars:
 
 ![http://seaborn.pydata.org/_images/seaborn-barplot-9.png](img/ef011fca38d3c55dde21ee8363e93e61.jpg)
 
-Use `hue` without changing bar position or width:
+在不改变条柱的位置或者宽度的前提下，使用 `hue` :
 
 ```py
 >>> tips["weekend"] = tips["day"].isin(["Sat", "Sun"])
@@ -217,7 +217,7 @@ Use `hue` without changing bar position or width:
 
 ![http://seaborn.pydata.org/_images/seaborn-barplot-11.png](img/4922c693b75b7656b2f16f8fd2dd6509.jpg)
 
-用 `plt.bar` keyword arguments to further change the aesthetic:
+用 `plt.bar` 关键字参数进一步改变图表的样式：
 
 ```py
 >>> ax = sns.barplot("day", "total_bill", data=tips,