diff --git a/app/model.py b/app/model/__init__.py
similarity index 89%
rename from app/model.py
rename to app/model/__init__.py
index bc8a08a..9526313 100644
--- a/app/model.py
+++ b/app/model/__init__.py
@@ -1,7 +1,7 @@
 from pony.orm import *
 
 db = Database()
-db.bind("sqlite", "./static/wordfreqapp.db", create_db=True)  # bind sqlite file
+db.bind("sqlite", "../static/wordfreqapp.db", create_db=True)  # bind sqlite file
 
 
 class User(db.Entity):
diff --git a/app/model/article.py b/app/model/article.py
new file mode 100644
index 0000000..a3b4bf7
--- /dev/null
+++ b/app/model/article.py
@@ -0,0 +1,34 @@
+from model import *
+from datetime import datetime
+
+def add_article(content, source="manual_input", level="5", question="No question"):
+    with db_session:
+        # add one article to sqlite
+        Article(
+            text=content,
+            source=source,
+            date=datetime.now().strftime("%-d %b %Y"),  # format style of `5 Oct 2022`
+            level=level,
+            question=question,
+        )
+
+
+def delete_article_by_id(article_id):
+    article_id &= 0xFFFFFFFF  # max 32 bits
+    with db_session:
+        article = Article.select(article_id=article_id)
+        if article:
+            article.first().delete()
+
+
+def get_number_of_articles():
+    with db_session:
+        return len(Article.select()[:])
+
+
+def get_page_articles(num, size):
+    with db_session:
+        return [
+            x
+            for x in Article.select().order_by(desc(Article.article_id)).page(num, size)
+        ]
diff --git a/app/model/user.py b/app/model/user.py
new file mode 100644
index 0000000..6c030c2
--- /dev/null
+++ b/app/model/user.py
@@ -0,0 +1,19 @@
+from model import *
+from Login import md5
+
+def get_users():
+    with db_session:
+        return User.select().order_by(User.name)[:]
+
+
+def update_password_by_username(username, password="123456"):
+    with db_session:
+        user = User.select(name=username)
+        if user:
+            user.first().password = md5(username + password)
+
+def update_expiry_time_by_username(username, expiry_time="20230323"):
+    with db_session:
+        user = User.select(name=username)
+        if user:
+            user.first().expiry_date = expiry_time