diff --git a/.gitignore b/.gitignore
index 68ca39690..4bd4b80b0 100644
--- a/.gitignore
+++ b/.gitignore
@@ -11,8 +11,6 @@ tex2pdf*
 .coverage
 .idea
 .vscode
-02_crowsnest/crowsnest.py
-03_picnic/picnic.py
 04_jump_the_five/jump.py
 05_howler/howler.py
 06_wc/wc.py
diff --git a/01_hello/hello.py b/01_hello/hello.py
new file mode 100755
index 000000000..9250aa78f
--- /dev/null
+++ b/01_hello/hello.py
@@ -0,0 +1,28 @@
+#!/Users/yida.wang/miniconda3/envs/py39/bin/python3
+"""
+Author:  Yida Wang <yidaalex.wang@gmail.com>
+Purpose: Say hello
+"""
+
+import argparse
+
+
+def get_args():
+    """Get the command-line arguments"""
+
+    parser = argparse.ArgumentParser(description='Say hello')
+    parser.add_argument('-n', '--name', metavar='name',
+                        default='World', help='Name to greet')
+    args = parser.parse_args()
+    return args
+
+
+def main():
+    """Make a jazz noise here"""
+
+    args = get_args()
+    print('Hello, ' + args.name + '!')
+
+
+if __name__ == '__main__':
+    main()
diff --git a/01_hello/hello2.py b/01_hello/hello2.py
new file mode 100755
index 000000000..85642e0a1
--- /dev/null
+++ b/01_hello/hello2.py
@@ -0,0 +1,72 @@
+#!/usr/bin/env python3
+"""
+Author : Yida Wang <yidaalex.wang@gmail.com>
+Date   : 2021-06-27
+Purpose: Rock the Casbah
+"""
+
+import argparse
+
+
+# --------------------------------------------------
+def get_args():
+    """Get command-line arguments"""
+
+    parser = argparse.ArgumentParser(
+        description='Rock the Casbah',
+        formatter_class=argparse.ArgumentDefaultsHelpFormatter)
+
+    parser.add_argument('positional',
+                        metavar='str',
+                        help='A positional argument')
+
+    parser.add_argument('-a',
+                        '--arg',
+                        help='A named string argument',
+                        metavar='str',
+                        type=str,
+                        default='')
+
+    parser.add_argument('-i',
+                        '--int',
+                        help='A named integer argument',
+                        metavar='int',
+                        type=int,
+                        default=0)
+
+    parser.add_argument('-f',
+                        '--file',
+                        help='A readable file',
+                        metavar='FILE',
+                        type=argparse.FileType('rt'),
+                        default=None)
+
+    parser.add_argument('-o',
+                        '--on',
+                        help='A boolean flag',
+                        action='store_true')
+
+    return parser.parse_args()
+
+
+# --------------------------------------------------
+def main():
+    """Make a jazz noise here"""
+
+    args = get_args()
+    str_arg = args.arg
+    int_arg = args.int
+    file_arg = args.file
+    flag_arg = args.on
+    pos_arg = args.positional
+
+    print(f'str_arg = "{str_arg}"')
+    print(f'int_arg = "{int_arg}"')
+    print('file_arg = "{}"'.format(file_arg.name if file_arg else ''))
+    print(f'flag_arg = "{flag_arg}"')
+    print(f'positional = "{pos_arg}"')
+
+
+# --------------------------------------------------
+if __name__ == '__main__':
+    main()
diff --git a/02_crowsnest/crowsnest.py b/02_crowsnest/crowsnest.py
new file mode 100755
index 000000000..dc7e81dac
--- /dev/null
+++ b/02_crowsnest/crowsnest.py
@@ -0,0 +1,37 @@
+#!/usr/bin/env python3
+"""
+Author : Yida Wang <yidaalex.wang@gmail.com>
+Date   : 2021-07-01
+Purpose: Crow's Nest
+"""
+
+import argparse
+
+
+# --------------------------------------------------
+def get_args():
+    """Get command-line arguments"""
+
+    parser = argparse.ArgumentParser(
+        description='Crow\'s Nest -- choose the correct article',
+        formatter_class=argparse.ArgumentDefaultsHelpFormatter)
+
+    parser.add_argument('word', metavar='word', help='A word')
+
+    return parser.parse_args()
+
+
+# --------------------------------------------------
+def main():
+    """Make a jazz noise here"""
+
+    args = get_args()
+    word = args.word
+    article = 'an' if word[0].lower() in 'aeiou' else 'a'
+
+    print(f'Ahoy, Captain, {article} {word} off the larboard bow!')
+
+
+# --------------------------------------------------
+if __name__ == '__main__':
+    main()
diff --git a/03_picnic/picnic.py b/03_picnic/picnic.py
new file mode 100755
index 000000000..a054b143e
--- /dev/null
+++ b/03_picnic/picnic.py
@@ -0,0 +1,58 @@
+#!/usr/bin/env python3
+"""
+Author : Yida Wang <yidaalex.wang@gmail.com>
+Date   : 2021-07-02
+Purpose: Picnic game
+"""
+
+import argparse
+
+
+# --------------------------------------------------
+def get_args():
+    """Get command-line arguments"""
+
+    parser = argparse.ArgumentParser(
+        description='Picnic game',
+        formatter_class=argparse.ArgumentDefaultsHelpFormatter)
+
+    parser.add_argument('items',
+                        metavar='str',
+                        nargs='+',
+                        help='Item(s) to bring')
+
+    parser.add_argument('-s',
+                        '--sorted',
+                        help='Sort the items',
+                        action='store_true')
+
+    return parser.parse_args()
+
+
+# --------------------------------------------------
+def main():
+    """Make a jazz noise here"""
+
+    args = get_args()
+    items = args.items
+    to_sort = args.sorted
+
+    num = len(items)
+
+    if to_sort:
+        items.sort()
+
+    bringing = ''
+    if num == 1:
+        bringing = items[0]
+    elif num == 2:
+        bringing = items[0] + ' and ' + items[1]
+    else:
+        bringing = ', '.join(items[:-1]) + ', and ' + items[-1]
+
+    print(f'You are bringing {bringing}.')
+
+
+# --------------------------------------------------
+if __name__ == '__main__':
+    main()