diff --git a/app/pickle_idea.py b/app/pickle_idea.py
index 45bd19a..2ad8992 100644
--- a/app/pickle_idea.py
+++ b/app/pickle_idea.py
@@ -54,12 +54,27 @@ def save_frequency_to_pickle(d, pickle_fname):
     pickle.dump(d2, f)
     f.close()
 
-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)
+'''
+Fixed function initializes a dictionary if file doesn't exist, increments word counts correctly, and 
+appends timestamps, preventing unintended count increases for previously marked words in subsequent uses.
+'''
+def unfamiliar(path, word):
+    try:
+        with open(path, "rb") as f:
+            dic = pickle.load(f)
+    except FileNotFoundError:
+        dic = {}  # Initialize an empty dictionary if the file doesn't exist
+
+    if word in dic:
+        dic[word][0] += 1  # Increment the count of the word
+    else:
+        dic[word] = [1, []]  # Initialize count to 1 and empty list for timestamps
+
+    dic[word][1].append(datetime.now().strftime('%Y%m%d%H%M'))  # Add timestamp
+
+    with open(path, "wb") as fp:
+        pickle.dump(dic, fp)
+
 
 def familiar(path,word):
     f = open(path,"rb")
diff --git a/app/test/helper.py b/app/test/helper.py
new file mode 100644
index 0000000..a6991d0
--- /dev/null
+++ b/app/test/helper.py
@@ -0,0 +1,48 @@
+import uuid
+from selenium.webdriver.support.ui import WebDriverWait
+from selenium.webdriver.support import expected_conditions as EC
+from selenium.common.exceptions import UnexpectedAlertPresentException, NoAlertPresentException
+from selenium.webdriver.common.by import By
+
+def signup(URL, driver):
+    username = 'TestUser' + str(uuid.uuid1()).split('-')[0].title()
+    password = '[Abc+123]'
+
+    driver.get(URL)
+    
+    try:
+        # Click the register link
+        register_link = WebDriverWait(driver, 10).until(
+            EC.element_to_be_clickable((By.LINK_TEXT, '注册'))
+        )
+        register_link.click()
+        
+        # Fill the registration form
+        username_field = WebDriverWait(driver, 10).until(
+            EC.presence_of_element_located((By.ID, 'username'))
+        )
+        username_field.send_keys(username)
+
+        password_field = driver.find_element(By.ID, 'password')
+        password_field.send_keys(password)
+
+        confirm_password_field = driver.find_element(By.ID, 'password2')
+        confirm_password_field.send_keys(password)
+
+        # Click the register button
+        register_button = driver.find_element(By.CLASS_NAME, 'btn')
+        register_button.click()
+
+        # Handle possible alert
+        try:
+            WebDriverWait(driver, 1).until(EC.alert_is_present())
+            alert = driver.switch_to.alert
+            alert.accept()
+        except (UnexpectedAlertPresentException, NoAlertPresentException):
+            pass
+        
+        return username, password
+    
+    except Exception as e:
+        print(f"An error occurred: {e}")
+        return None, None
\ No newline at end of file
diff --git a/app/test/test_bug518_mponeja.py b/app/test/test_bug518_mponeja.py
new file mode 100644
index 0000000..2f137b5
--- /dev/null
+++ b/app/test/test_bug518_mponeja.py
@@ -0,0 +1,107 @@
+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)
+        time.sleep(5)
+
+        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)
+
+
+
+        #add new words
+        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(5)
+
+        #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)
+      
+      
+        #current count after adding new words
+        current_unfamiliar_count = driver.find_element(By.XPATH, '//a[contains(@class, "btn-warning") and text()="不熟悉"]')
+        current_unfamiliar_count = int(unfamiliar_btn.text.split('(')[1].split(')')[0])
+        print(f"Unfamiliar word count: {current_unfamiliar_count}")
+        time.sleep(3)
+
+
+        # 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