Checkbox: fix confused document (#2788)

examples/docs/en-US/checkbox.md

@@ -11,8 +11,8 @@
         isValid: 'valid',
         checkAll: false,
         cities: cityOptions,
-        checkedCities: ['上海', '北京'],
-        isIndeterminate: false
+        checkedCities: ['ShangHai', 'BeiJing'],
+        isIndeterminate: true
       };
     },
     methods: {
@@ -34,7 +34,7 @@
 
 ## Checkbox
 
-A group of options for multiple choices.
+A group of options for multiple choices. content in that tag will become the description following the button of the checkbox.
 
 ### Basic usage
 
@@ -87,7 +87,7 @@ Disabled state for checkbox.
 
 It is used for multiple checkboxes which are bound in one group, and indicates whether one option is selected by checking if it is checked.
 
-:::demo `checkbox-group` element can manage multiple checkboxes in one group by using `v-model` which is bound as an `Array`. `label` can modify the description following the button of the checkbox. It is also the value of the checkbox. `label` corresponds with the element values in the array. It is selected if the specified value exists in the array, and vice versa.
+:::demo `checkbox-group` element can manage multiple checkboxes in one group by using `v-model` which is bound as an `Array`. in `el-checkbox` element, `label` is the value of the checkbox. While no content in that tag, it's also modify the description following the button of the checkbox. `label` also corresponds with the element values in the array. It is selected if the specified value exists in the array, and vice versa.
 
 ```html
 <template>
@@ -132,9 +132,9 @@ The `indeterminate` property can help you to achieve a 'check all' effect.
     data() {
       return {
         checkAll: true,
-        checkedCities: [],
+        checkedCities: ['ShangHai', 'BeiJing'],
         cities: cityOptions,
-        isIndeterminate: false
+        isIndeterminate: true
       };
     },
     methods: {

examples/docs/zh-CN/checkbox.md

@@ -12,7 +12,7 @@
         checkAll: false,
         cities: cityOptions,
         checkedCities: ['上海', '北京'],
-        isIndeterminate: false
+        isIndeterminate: true
       };
     },
     methods: {
@@ -21,7 +21,7 @@
       },
       handleCheckAllChange(event) {
         this.checkedCities = event.target.checked ? cityOptions : [];
-        this.isIndeterminate = false;
+        this.isIndeterminate = true;
       },
       handleCheckedCitiesChange(value) {
         let checkedCount = value.length;
@@ -48,7 +48,7 @@
 
 ### 基础用法
 
-单独使用可以表示两种状态之间的切换
+单独使用可以表示两种状态之间的切换，写在标签中的内容为 checkbox 按钮后的介绍。
 
 :::demo 在`el-checkbox`元素中定义`v-model`绑定变量，单一的`checkbox`中，默认绑定变量的值会是`Boolean`，选中为`true`。
 
@@ -97,7 +97,7 @@
 
 适用于多个勾选框绑定到同一个数组的情景，通过是否勾选来表示这一组选项中选中的项。
 
-:::demo `checkbox-group`元素能把多个 checkbox 管理为一组，只需要在 Group 中使用`v-model`绑定`Array`类型的变量即可，`label`属性除了改变 checkbox 按钮后的介绍外，同时也是该 checkbox 对应的值，`label`与数组中的元素值相对应，如果存在指定的值则为选中状态，否则为不选中。
+:::demo `checkbox-group`元素能把多个 checkbox 管理为一组，只需要在 Group 中使用`v-model`绑定`Array`类型的变量即可。 `el-checkbox` 的 `label`属性是该 checkbox 对应的值，若该标签中无内容，则该属性也充当 checkbox 按钮后的介绍。`label`与数组中的元素值相对应，如果存在指定的值则为选中状态，否则为不选中。
 
 ```html
 <template>
@@ -142,9 +142,9 @@
     data() {
       return {
         checkAll: true,
-        checkedCities: [],
+        checkedCities: ['上海', '北京'],
         cities: cityOptions,
-        isIndeterminate: false
+        isIndeterminate: true
       };
     },
     methods: {