diff --git "a/21\345\272\204\344\272\221/\344\275\234\344\270\232/2022-11-24\344\272\213\344\273\266_\345\244\232\351\200\211\346\241\206.html" "b/21\345\272\204\344\272\221/\344\275\234\344\270\232/2022-11-24\344\272\213\344\273\266_\345\244\232\351\200\211\346\241\206.html"
new file mode 100644
index 0000000000000000000000000000000000000000..6d0ab4beb724f4cf05cf7a7a05ccb1cc7e228b7b
--- /dev/null
+++ "b/21\345\272\204\344\272\221/\344\275\234\344\270\232/2022-11-24\344\272\213\344\273\266_\345\244\232\351\200\211\346\241\206.html"
@@ -0,0 +1,39 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Document</title>
+</head>
+<body>
+    <div id="div">
+        <input type="checkbox" name="a" value="语文">语文
+        <input type="checkbox" name="a" value="数学">数学
+        <input type="checkbox" name="a" value="英语">英语
+        <input type="checkbox" name="a" value="物理">物理
+        <input type="checkbox" name="a" value="历史">历史
+    </div>
+    <p></p>
+    <script>
+        var div =document.getElementById('div');
+        var input=document.querySelectorAll('input');
+        var length=input.length;
+        var p=document.querySelector('p');
+        div.onchange=function (){
+             var text='';
+            for (let i = 0; i < length; i++) {
+            if (input[i].checked==true) {
+                text+=input[i].value+' ';
+            }
+        }
+        if(text==''){
+            p.innerText='';
+        }else{
+           p.innerText=`您选择了${text}`; 
+        }
+        
+        }
+    </script>
+</body>
+</html>
\ No newline at end of file
diff --git "a/21\345\272\204\344\272\221/\344\275\234\344\270\232/2022-11-24\344\272\213\344\273\266_\351\274\240\346\240\207\346\217\220\347\244\272.html" "b/21\345\272\204\344\272\221/\344\275\234\344\270\232/2022-11-24\344\272\213\344\273\266_\351\274\240\346\240\207\346\217\220\347\244\272.html"
new file mode 100644
index 0000000000000000000000000000000000000000..86998ac20215a753a10230ef7f6c66ee67284d99
--- /dev/null
+++ "b/21\345\272\204\344\272\221/\344\275\234\344\270\232/2022-11-24\344\272\213\344\273\266_\351\274\240\346\240\207\346\217\220\347\244\272.html"
@@ -0,0 +1,24 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Document</title>
+</head>
+<body>
+    <div>
+        <input type="text" >
+    </div>
+    <script>
+        var input=document.querySelector('input');
+        console.dir(input);
+        input.onmouseover=function(){
+           this.placeholder='aaa'
+        }
+        input.onmouseout=function(){
+            this.placeholder=''
+        }
+    </script>
+</body>
+</html>
\ No newline at end of file
