diff --git a/src/extra_interview_problems/basic_examples/example_comp_lists.py b/src/extra_interview_problems/basic_examples/example_comp_lists.py
new file mode 100644
index 0000000..cb1fd16
--- /dev/null
+++ b/src/extra_interview_problems/basic_examples/example_comp_lists.py
@@ -0,0 +1,26 @@
+Bad:
+
+# Filter elements greater than 4
+a = [3, 4, 5]
+b = []
+for i in a:
+    if i > 4:
+        b.append(i)
+Good:
+
+a = [3, 4, 5]
+b = [i for i in a if i > 4]
+# Or:
+b = filter(lambda x: x > 4, a)
+Bad:
+
+# Add three to all list members.
+a = [3, 4, 5]
+for i in range(len(a)):
+    a[i] += 3
+Good:
+
+a = [3, 4, 5]
+a = [i + 3 for i in a]
+# Or:
+a = map(lambda i: i + 3, a)
\ No newline at end of file
diff --git a/src/extra_interview_problems/basic_examples/string_format.py b/src/extra_interview_problems/basic_examples/string_format.py
new file mode 100644
index 0000000..a5c03b6
--- /dev/null
+++ b/src/extra_interview_problems/basic_examples/string_format.py
@@ -0,0 +1,6 @@
+foo = 'foo'
+bar = 'bar'
+
+print '%s%s' % (foo, bar) # It is OK
+print '{0}{1}'.format(foo, bar) # It is better
+print '{foo}{bar}'.format(foo=foo, bar=bar) # It is best
\ No newline at end of file