add a short section about chaining querysets

Author: donaldharvey

en/django_orm/README.md

@@ -130,6 +130,15 @@ We can also reverse the ordering by adding `-` at the beginning:
     >>> Post.objects.order_by('-created_date')
     [<Post: 4th title of post>,  <Post: My 3rd post!>, <Post: Post number 2>, <Post: Sample title>]
 
+
+### Chaining querysets
+
+You can also combine QuerySets by **chaining** them together:
+
+    >>> Post.objects.filter(published_date__lte=timezone.now()).order_by('published_date')
+
+This is really powerful and lets you write quite complex queries.
+
 Cool! You're now ready for the next part! To close the shell, type this:
 
     >>> exit()