diff --git a/app/Login.py b/app/Login.py
index 17d92fa..cd3ee22 100644
--- a/app/Login.py
+++ b/app/Login.py
@@ -1,6 +1,8 @@
 import hashlib
 import string
 from datetime import datetime, timedelta
+import unicodedata
+
 
 def md5(s):
     '''
@@ -11,14 +13,16 @@ def md5(s):
     h = hashlib.md5(s.encode(encoding='utf-8'))
     return h.hexdigest()
 
+
 # import model.user after the defination of md5(s) to avoid circular import
 from model.user import get_user_by_username, insert_user, update_password_by_username
 
 path_prefix = '/var/www/wordfreq/wordfreq/'
 path_prefix = './'  # comment this line in deployment
 
-def verify_pass(newpass,oldpass):
-    if(newpass==oldpass):
+
+def verify_pass(newpass, oldpass):
+    if (newpass == oldpass):
         return True
 
 
@@ -30,7 +34,7 @@ def verify_user(username, password):
 
 def add_user(username, password):
     start_date = datetime.now().strftime('%Y%m%d')
-    expiry_date = (datetime.now() + timedelta(days=30)).strftime('%Y%m%d') # will expire after 30 days
+    expiry_date = (datetime.now() + timedelta(days=30)).strftime('%Y%m%d')  # will expire after 30 days
     # 将用户名和密码一起加密，以免暴露不同用户的相同密码
     password = md5(username + password)
     insert_user(username=username, password=password, start_date=start_date, expiry_date=expiry_date)
@@ -52,7 +56,7 @@ def change_password(username, old_password, new_password):
     if not verify_user(username, old_password):  # 旧密码错误
         return False
     # 将用户名和密码一起加密，以免暴露不同用户的相同密码
-    if verify_pass(new_password,old_password): #新旧密码一致
+    if verify_pass(new_password, old_password):  #新旧密码一致
         return False
     update_password_by_username(username, new_password)
     return True
@@ -65,30 +69,64 @@ def get_expiry_date(username):
     else:
         return user.expiry_date
 
+
 class UserName:
     def __init__(self, username):
         self.username = username
 
+    def contains_chinese(self):
+        for char in self.username:
+            # Check if the character is in the CJK (Chinese, Japanese, Korean) Unicode block
+            if unicodedata.name(char).startswith('CJK UNIFIED IDEOGRAPH'):
+                return True
+        return False
+
     def validate(self):
         if len(self.username) > 20:
             return f'{self.username} is too long.  The user name cannot exceed 20 characters.'
-        if self.username.startswith('.'): # a user name must not start with a dot
+        if self.username.startswith('.'):  # a user name must not start with a dot
             return 'Period (.) is not allowed as the first letter in the user name.'
-        if ' ' in self.username: # a user name must not include a whitespace
+        if ' ' in self.username:  # a user name must not include a whitespace
             return 'Whitespace is not allowed in the user name.'
-        for c in self.username: # a user name must not include special characters, except non-leading periods or underscores
+        for c in self.username:  # a user name must not include special characters, except non-leading periods or underscores
             if c in string.punctuation and c != '.' and c != '_':
                 return f'{c} is not allowed in the user name.'
-        if self.username in ['signup', 'login', 'logout', 'reset', 'mark', 'back', 'unfamiliar', 'familiar', 'del', 'admin']:
+        if self.username in ['signup', 'login', 'logout', 'reset', 'mark', 'back', 'unfamiliar', 'familiar', 'del',
+                             'admin']:
             return 'You used a restricted word as your user name.  Please come up with a better one.'
+        if self.contains_chinese():
+            return 'Chinese characters are not allowed in the user name.'
+        return 'OK'
 
+
+class Password:
+    def __init__(self, password):
+        self.password = password
+
+    def contains_chinese(self):
+        for char in self.password:
+            # Check if the character is in the CJK (Chinese, Japanese, Korean) Unicode block
+            if unicodedata.name(char).startswith('CJK UNIFIED IDEOGRAPH'):
+                return True
+        return False
+
+    def validate(self):
+        if len(self.password) < 4:
+            return 'Password must be at least 4 characters long.'
+        if ' ' in self.password:
+            return 'Password cannot contain spaces.'
+        if self.contains_chinese():
+            return 'Chinese characters are not allowed in the password.'
         return 'OK'
 
 
 class WarningMessage:
-    def __init__(self, s):
+    def __init__(self, s, type='username'):
         self.s = s
+        self.type = type
 
     def __str__(self):
-        return UserName(self.s).validate()
-
+        if self.type == 'username':
+            return UserName(self.s).validate()
+        if self.type == 'password':
+            return Password(self.s).validate()
diff --git a/app/static/js/fillword.js b/app/static/js/fillword.js
index 111027a..3e88107 100644
--- a/app/static/js/fillword.js
+++ b/app/static/js/fillword.js
@@ -21,14 +21,19 @@ function fillInWord() {
     localStorage.setItem('selectedWords', element.value);
 }
 
-document.getElementById("text-content").addEventListener("click", fillInWord, false);
+if (document.getElementById("text-content")) {
+    document.getElementById("text-content").addEventListener("click", fillInWord, false);
+}
 
 const sliderValue = document.getElementById("rangeValue");
 const inputSlider = document.getElementById("rangeComponent");
-inputSlider.oninput = () => {
-    let value = inputSlider.value;
-    sliderValue.textContent = value + '×';
-};
+
+if (inputSlider) {
+    inputSlider.oninput = () => {
+	let value = inputSlider.value;
+	sliderValue.textContent = value + '×';
+    };
+}
 
 function onReadClick() {
     isRead = !isRead;
diff --git a/app/static/js/highlight.js b/app/static/js/highlight.js
index 7c3a112..7a1df5d 100644
--- a/app/static/js/highlight.js
+++ b/app/static/js/highlight.js
@@ -9,11 +9,13 @@ function cancelBtnHandler() {
 }
 
 function showBtnHandler() {
-    document.getElementById("text-content").removeEventListener("click", fillInWord2, false);
-    document.getElementById("text-content").removeEventListener("touchstart", fillInWord2, false);
-    document.getElementById("text-content").addEventListener("click", fillInWord, false);
-    document.getElementById("text-content").addEventListener("touchstart", fillInWord, false);
-    highLight();
+    if (document.getElementById("text-content")) {
+	document.getElementById("text-content").removeEventListener("click", fillInWord2, false);
+	document.getElementById("text-content").removeEventListener("touchstart", fillInWord2, false);
+	document.getElementById("text-content").addEventListener("click", fillInWord, false);
+	document.getElementById("text-content").addEventListener("touchstart", fillInWord, false);
+	highLight();
+    }
 }
 function replaceWords(str, word) {
   let count = 0;
diff --git a/app/test/test_bug536_jiangwangzhe.py b/app/test/test_bug536_jiangwangzhe.py
new file mode 100644
index 0000000..4862486
--- /dev/null
+++ b/app/test/test_bug536_jiangwangzhe.py
@@ -0,0 +1,88 @@
+from selenium.webdriver.common.alert import Alert
+from selenium.webdriver.common.by import By
+from selenium.webdriver.support.ui import WebDriverWait
+from selenium.webdriver.support import expected_conditions as EC
+
+
+# 对用户名不能为中文进行测试
+def test_register_username_with_chinese(driver, URL):
+    try:
+        driver.get(URL + "/signup")
+
+        # 等待用户名输入框出现
+        username_elem = WebDriverWait(driver, 10).until(
+            EC.presence_of_element_located((By.ID, 'username'))
+        )
+        username_elem.send_keys("测试用户")  # 输入中文用户名
+
+        # 等待密码输入框出现
+        password_elem = WebDriverWait(driver, 10).until(
+            EC.presence_of_element_located((By.ID, 'password'))
+        )
+        password_elem.send_keys("validPassword123")  # 输入有效密码
+
+        # 等待确认密码输入框出现
+        password2_elem = WebDriverWait(driver, 10).until(
+            EC.presence_of_element_located((By.ID, 'password2'))
+        )
+        password2_elem.send_keys("validPassword123")  # 输入有效确认密码
+
+        # 等待注册按钮出现并点击
+        signup_button = WebDriverWait(driver, 10).until(
+            EC.element_to_be_clickable((By.XPATH, '//button[@onclick="signup()"]'))
+        )
+        signup_button.click()
+
+        # 等待警告框出现并接受
+        WebDriverWait(driver, 10).until(EC.alert_is_present())
+        alert = driver.switch_to.alert
+        alert_text = alert.text
+        print(f"警告文本: {alert_text}")
+        assert alert_text == "Chinese characters are not allowed in the user name."  # 根据实际的警告文本进行断言
+        alert.accept()
+
+    except Exception as e:
+        print(f"发生错误: {e}")
+        raise
+
+
+# 对注册时密码不能是中文进行测试
+def test_register_password_with_chinese(driver, URL):
+    try:
+        driver.get(URL + "/signup")
+
+        # 等待用户名输入框出现
+        username_elem = WebDriverWait(driver, 10).until(
+            EC.presence_of_element_located((By.ID, 'username'))
+        )
+        username_elem.send_keys("validUsername123")  # 输入有效用户名
+
+        # 等待密码输入框出现
+        password_elem = WebDriverWait(driver, 10).until(
+            EC.presence_of_element_located((By.ID, 'password'))
+        )
+        password_elem.send_keys("测试密码")  # 输入中文密码
+
+        # 等待确认密码输入框出现
+        password2_elem = WebDriverWait(driver, 10).until(
+            EC.presence_of_element_located((By.ID, 'password2'))
+        )
+        password2_elem.send_keys("测试密码")  # 输入中文确认密码
+
+        # 等待注册按钮出现并点击
+        signup_button = WebDriverWait(driver, 10).until(
+            EC.element_to_be_clickable((By.XPATH, '//button[@onclick="signup()"]'))
+        )
+        signup_button.click()
+
+        # 等待警告框出现并接受
+        WebDriverWait(driver, 10).until(EC.alert_is_present())
+        alert = driver.switch_to.alert
+        alert_text = alert.text
+        print(f"警告文本: {alert_text}")
+        assert alert_text == "Chinese characters are not allowed in the password."  # 根据实际的警告文本进行断言
+        alert.accept()
+
+    except Exception as e:
+        print(f"发生错误: {e}")
+        raise