diff --git a/app/Article.py b/app/Article.py
index e0f006a..b4df54c 100644
--- a/app/Article.py
+++ b/app/Article.py
@@ -32,17 +32,17 @@ def get_article_body(s):
     return '\n'.join(lst)
 
 
-def get_today_article(user_word_list, existing_articles):
+def get_today_article(user_word_list, had_read_articles):
     rq = RecordQuery(path_prefix + 'static/wordfreqapp.db')
-    if existing_articles is None:
-        existing_articles = {
+    if had_read_articles is None:
+        had_read_articles = {
             "index" : 0,  # 为 article_ids 的索引
             "article_ids": []  # 之前显示文章的id列表，越后越新
         }
-    if existing_articles["index"] > len(existing_articles["article_ids"])-1:
+    if had_read_articles["index"] > len(had_read_articles["article_ids"])-1:
         rq.instructions("SELECT * FROM article")
     else:
-        rq.instructions('SELECT * FROM article WHERE article_id=%d' % (existing_articles["article_ids"][existing_articles["index"]]))
+        rq.instructions('SELECT * FROM article WHERE article_id=%d' % (had_read_articles["article_ids"][had_read_articles["index"]]))
     rq.do()
     result = rq.get_results()
     random.shuffle(result)
@@ -56,19 +56,19 @@ def get_today_article(user_word_list, existing_articles):
     d_user = load_freq_history(user_word_list)
     user_level = user_difficulty_level(d_user, d3)  # more consideration as user's behaviour is dynamic. Time factor should be considered.
     text_level = 0
-    if existing_articles["index"] > len(existing_articles["article_ids"])-1:  # 下一篇
+    if had_read_articles["index"] > len(had_read_articles["article_ids"])-1:  # 下一篇
         flag_get_article = False
         for reading in result:
             text_level = text_difficulty_level(reading['text'], d3)
             factor = random.gauss(0.8,
                                   0.1)  # a number drawn from Gaussian distribution with a mean of 0.8 and a stand deviation of 1
-            if reading['article_id'] not in existing_articles["article_ids"] and within_range(text_level, user_level, (8.0 - user_level) * factor):  # 新的文章之前没有出现过且符合一定范围的水平
+            if reading['article_id'] not in had_read_articles["article_ids"] and within_range(text_level, user_level, (8.0 - user_level) * factor):  # 新的文章之前没有出现过且符合一定范围的水平
                 d = reading
-                existing_articles["article_ids"].append(d['article_id'])  # 列表添加新的文章id；下面进行
+                had_read_articles["article_ids"].append(d['article_id'])  # 列表添加新的文章id；下面进行
                 flag_get_article = True
                 break
         if not flag_get_article:
-            existing_articles["index"] -= 1
+            had_read_articles["index"] -= 1
     else:  # 上一篇
         d = random.choice(result)
         text_level = text_difficulty_level(d['text'], d3)
@@ -86,7 +86,7 @@ def get_today_article(user_word_list, existing_articles):
             "answer": get_answer_part(d['question'])
         }
 
-    return existing_articles, today_article
+    return had_read_articles, today_article
 
 
 def load_freq_history(path):
diff --git a/app/account_service.py b/app/account_service.py
index c1bd64c..8de9a03 100644
--- a/app/account_service.py
+++ b/app/account_service.py
@@ -37,7 +37,7 @@ def signup():
                 session[username] = username
                 session['username'] = username
                 session['expiry_date'] = get_expiry_date(username)
-                session['existing_articles'] = None
+                session['had_read_articles'] = None
                 return jsonify({'status': '2'})
             else:
                 return jsonify({'status': '1'})
@@ -66,7 +66,7 @@ def login():
             session['username'] = username
             user_expiry_date = get_expiry_date(username)
             session['expiry_date'] = user_expiry_date
-            session['existing_articles'] = None
+            session['had_read_articles'] = None
             return jsonify({'status': '1'})
         else:
             return jsonify({'status': '0'})
diff --git a/app/templates/userpage_get.html b/app/templates/userpage_get.html
index 298b559..428bb3b 100644
--- a/app/templates/userpage_get.html
+++ b/app/templates/userpage_get.html
@@ -45,7 +45,7 @@
 {#    {% endfor %}#}
 
     <a class="btn btn-success" href="/{{ username }}/reset" role="button"> 下一篇 Next Article </a>
-    {% if session.get('existing_articles') != None and session.get('existing_articles')["index"] !=0 %}
+    {% if session.get('had_read_articles') != None and session.get('had_read_articles')["index"] !=0 %}
         <a class="btn btn-success" href="/{{ username }}/back" role="button"> 上一篇 Previous Article </a>
     {% endif %}
 
diff --git a/app/user_service.py b/app/user_service.py
index 8d1dbfc..61b129d 100644
--- a/app/user_service.py
+++ b/app/user_service.py
@@ -30,9 +30,9 @@ def user_reset(username):
     :return: 返回页面内容
     '''
     if request.method == 'GET':
-        existing_articles = session.get("existing_articles")
-        existing_articles["index"] += 1
-        session["existing_articles"] = existing_articles
+        had_read_articles = session.get("had_read_articles")
+        had_read_articles["index"] += 1
+        session["had_read_articles"] = had_read_articles
         return redirect(url_for('user_bp.userpage', username=username))
     else:
         return 'Under construction'
@@ -45,9 +45,9 @@ def user_back(username):
     :return: 返回页面内容
     '''
     if request.method == 'GET':
-        existing_articles = session.get("existing_articles")
-        existing_articles["index"] -= 1
-        session["existing_articles"] = existing_articles
+        had_read_articles = session.get("had_read_articles")
+        had_read_articles["index"] -= 1
+        session["had_read_articles"] = had_read_articles
         return redirect(url_for('user_bp.userpage', username=username))
 
 
@@ -134,8 +134,8 @@ def userpage(username):
         words = ''
         for x in lst3:
             words += x[0] + ' '
-        existing_articles, today_article = get_today_article(user_freq_record, session.get('existing_articles'))
-        session['existing_articles'] = existing_articles
+        had_read_articles, today_article = get_today_article(user_freq_record, session.get('had_read_articles'))
+        session['had_read_articles'] = had_read_articles
         # 通过 today_article，加载前端的显示页面
         return render_template('userpage_get.html',
                                username=username,