diff --git a/EnglishPal b/EnglishPal
new file mode 160000
index 0000000..8cbc7c9
--- /dev/null
+++ b/EnglishPal
@@ -0,0 +1 @@
+Subproject commit 8cbc7c9a0ce543db48f80a743c4168ca847ca500
diff --git a/app/pickle_idea.py b/app/pickle_idea.py
index 45bd19a..c172c32 100644
--- a/app/pickle_idea.py
+++ b/app/pickle_idea.py
@@ -54,12 +54,19 @@ def save_frequency_to_pickle(d, pickle_fname):
     pickle.dump(d2, f)
     f.close()
 
-def unfamiliar(path,word):
-    f = open(path,"rb")
+def unfamiliar(path, word):
+    f = open(path, "rb")
     dic = pickle.load(f)
-    dic[word] += [datetime.now().strftime('%Y%m%d%H%M')]
-    fp = open(path,"wb")
-    pickle.dump(dic,fp)
+    if word in dic:
+        if len(dic[word]) <= 16:  # Check if the length of the list is less than 16
+            dic[word].append(datetime.now().strftime('%Y%m%d%H%M'))
+        else:
+            dic[word].append(datetime.now().strftime('%Y%m%d%H%M'))
+    else:
+        dic[word] = [datetime.now().strftime('%Y%m%d%H%M')]
+    f.close()
+    with open(path, "wb") as fp:
+        pickle.dump(dic, fp)
 
 def familiar(path,word):
     f = open(path,"rb")
diff --git a/app/templates/userpage_get.html b/app/templates/userpage_get.html
index 57461c1..88cfdd6 100644
--- a/app/templates/userpage_get.html
+++ b/app/templates/userpage_get.html
@@ -232,6 +232,7 @@
                     update(data['today_article']);
                     check_pre(data['visited_articles']);
                     check_next(data['result_of_generate_article']);
+                    toggleHighlighting();
                 }
             }
         });
@@ -245,6 +246,7 @@
                 if(data['today_article']){
                     update(data['today_article']);
                     check_pre(data['visited_articles']);
+                    toggleHighlighting();
                 }
             }
         });
diff --git a/app/test/conftest.py b/app/test/conftest.py
index ed4186c..aefb718 100644
--- a/app/test/conftest.py
+++ b/app/test/conftest.py
@@ -12,24 +12,5 @@ def URL():
 
 @pytest.fixture
 def driver():
-    return webdriver.Edge()  # follow the "End-to-end testing" section in README.md to install the web driver executable
-
-
-@pytest.fixture
-def restore_sqlite_database():
-    '''
-    Automatically restore SQLite database file app/db/wordfreqapp.db
-    using SQL statements from app/static/wordfreqapp.sql
-    '''
-    con = sqlite3.connect('../db/wordfreqapp.db')
-    with con:
-        con.executescript('DROP TABLE IF EXISTS user;')
-        con.executescript('DROP TABLE IF EXISTS article;')
-        con.executescript(open('../static/wordfreqapp.sql', encoding='utf8').read())
-    con.close()
-
-
-@pytest.fixture(autouse=True)
-def restart_englishpal(restore_sqlite_database):
-    (Path(__file__).parent / '../main.py').touch()
-    time.sleep(1)
+    my_driver = webdriver.Chrome()
+    return my_driver
diff --git a/app/test/test_bug518_esther.py b/app/test/test_bug518_esther.py
new file mode 100644
index 0000000..9814d2b
--- /dev/null
+++ b/app/test/test_bug518_esther.py
@@ -0,0 +1,112 @@
+import random
+import string
+import time
+
+from selenium.webdriver.common.by import By
+from selenium.webdriver.support.ui import WebDriverWait
+from selenium.webdriver.support import expected_conditions as EC
+
+from helper import signup
+
+def has_punctuation(s):
+    return any(c in string.punctuation for c in s)
+
+def login(driver, home, uname, password):
+    driver.get(home)
+    WebDriverWait(driver, 10).until(EC.element_to_be_clickable((By.LINK_TEXT, '登录'))).click()
+    driver.find_element(By.ID, 'username').send_keys(uname)
+    driver.find_element(By.ID, 'password').send_keys(password)
+    driver.find_element(By.XPATH, '//button[text()="登录"]').click()
+    WebDriverWait(driver, 10).until(EC.title_is(f"EnglishPal Study Room for {uname}"))
+
+
+def select_valid_word(driver):
+    elem = driver.find_element(By.ID, 'text-content')
+    essay_content = elem.text
+    valid_word = random.choice([word for word in essay_content.split() if len(word) >= 6 and not has_punctuation(
+        word) and 'font>' not in word and 'br>' not in word and 'p>' not in word])
+    driver.find_element(By.ID, 'selected-words').send_keys(valid_word)
+    return valid_word
+
+
+
+def select_more_words(driver):
+    elem = driver.find_element(By.ID, 'text-content')
+    essay_content = elem.text
+    valid_words = [word for word in essay_content.split() if len(word) >= 6 and not has_punctuation(
+        word) and 'font>' not in word and 'br>' not in word and 'p>' not in word]
+    words_to_send = ', '.join(valid_words[:7])
+    driver.find_element(By.ID, 'selected-words').send_keys(words_to_send)
+
+
+def test_unfamiliar_button(driver, URL):
+    try:
+        username, password = signup(URL, driver)
+        word = select_valid_word(driver)
+        
+        # Wait for the button to be clickable
+        time.sleep(8)
+       # Add selected word to the list of unfamiliar words
+        add_to_unfamiliar_button =  driver.find_element(By.XPATH, '//button[text()="把生词加入我的生词库"]')
+        add_to_unfamiliar_button.click()
+        # Wait for the page to update
+        time.sleep(3)
+
+        add_words_button =  driver.find_element(By.XPATH, '//button[text()="加入我的生词簿"]') # Replace with actual ID or selector
+        add_words_button.click()
+        # Wait for the page to update again
+        time.sleep(2)
+
+
+      # Check if the added word appears in the word container
+        word_container = driver.find_element(By.CLASS_NAME, 'word-container')
+        words = word_container.find_elements(By.TAG_NAME, 'p')
+        added_word_exists = any(word.text == word for word in words)
+        time.sleep(2)
+
+        # Mark word as unfamiliar
+        time.sleep(5)
+        for _ in range(16):
+            time.sleep(1)
+            unfamiliar_btn = driver.find_element(By.XPATH, '//a[contains(@class, "btn-warning") and text()="不熟悉"]')
+            unfamiliar_btn.click()
+        # Wait for the page to updatec
+        time.sleep(5)
+
+        word = select_more_words(driver)
+        add_to_unfamiliar_button =  driver.find_element(By.XPATH, '//button[text()="把生词加入我的生词库"]')
+        add_to_unfamiliar_button.click()
+            
+        time.sleep(3)
+
+        #add the words to the list of words
+        add_words_again =  driver.find_element(By.XPATH, '//button[text()="加入我的生词簿"]') # Replace with actual ID or selector
+        add_words_again.click()
+        # Wait for the page to update again
+        time.sleep(3)
+      
+      
+        # # Check if the number of unfamiliar words has increased
+        # unfamiliar_word_count = driver.find_element(By.ID, 'unfamiliar_word_count').text
+        # initial_count = int(unfamiliar_word_count)
+
+        # # Simulate adding more words to the list
+        # add_words_button = driver.find_element(By.ID, 'add_words_button')  # Replace with actual ID or selector
+        # add_words_button.click()
+
+        # # Wait for the page to update again
+        # time.sleep(2)
+
+        # # Verify that the number of unfamiliar words has decreased
+        # new_unfamiliar_word_count = driver.find_element(By.ID, 'unfamiliar_word_count').text
+        # assert int(new_unfamiliar_word_count) < initial_count, "Unfamiliar word count did not decrease as expected"
+
+        # Log out and close the browser
+        driver.find_element(By.XPATH, '//a[contains(@class, "btn-secondary") and text()="退出"]')
+        driver.execute_script("window.open('');window.close();")
+        WebDriverWait(driver, 2)
+        driver.execute_script("window.open('');")
+        driver.switch_to.window(driver.window_handles[-1])
+
+    finally:
+        driver.quit()
\ No newline at end of file
diff --git a/app/test/test_bug555_fangchen.py b/app/test/test_bug555_fangchen.py
new file mode 100644
index 0000000..d1edfb5
--- /dev/null
+++ b/app/test/test_bug555_fangchen.py
@@ -0,0 +1,43 @@
+import time
+import pytest
+import uuid
+from selenium import webdriver
+from selenium.webdriver import ActionChains
+from selenium.webdriver.common.by import By
+from selenium.webdriver.support.ui import WebDriverWait
+from selenium.webdriver.support import expected_conditions as EC
+from selenium.common.exceptions import UnexpectedAlertPresentException, NoAlertPresentException, NoSuchElementException, \
+    TimeoutException
+from conftest import URL
+driver = webdriver.Chrome()
+def test_bug555():
+    try:
+        driver.maximize_window()
+        base_url = "http://127.0.0.1:5000"
+        driver.get(base_url)
+        article = WebDriverWait(driver, 10).until(EC.element_to_be_clickable((By.ID, 'article')))
+        perform_actions_on_article(driver, article)
+
+        next_button = WebDriverWait(driver, 10).until(EC.element_to_be_clickable((By.ID, 'load_next_article')))
+        next_button.click()
+        print("Clicked next article button.")
+
+        prev_button = WebDriverWait(driver, 10).until(EC.element_to_be_clickable((By.ID, 'load_pre_article')))
+        prev_button.click()
+        print("Clicked previous article button.")
+
+    except (TimeoutException, NoSuchElementException) as e:
+        print(f"An error occurred: {e}")
+
+    finally:
+        driver.quit()
+        print("Driver closed.")
+
+def perform_actions_on_article(driver, article):
+    actions = ActionChains(driver)
+    actions.move_to_element(article)
+    actions.click_and_hold()
+    actions.move_by_offset(450, 200)
+    actions.release()
+    actions.perform()
+    print("Performed actions on article.")
\ No newline at end of file
diff --git a/mintty.2024-06-04_11-12-32.png b/mintty.2024-06-04_11-12-32.png
new file mode 100644
index 0000000..72ccafe
Binary files /dev/null and b/mintty.2024-06-04_11-12-32.png differ