From command mode, the x command deletes the character under the cursor. If you press x five times, you'll end up with:
Now press a, insert some text, followed by esc:
You can delete entire lines using the command dd (that is, press d twice in a row). If your cursor is on the second line, and you type dd,
To delete the word which the cursor is on, use the dw command. Place the cursor on the word ``good'', and type dw.
