Up to this point, you have mainly played notes using the first three fingers of the left hand. Some of the notes in this lesson are played at the 4th fret with the fourth finger of the left hand. The principle for playing with the fourth finger is the same as for playing with the other fingers. Use the very tip of the finger and keep the finger curved. If you have maintained correct left hand technique in your playing so far, you should have no trouble with these new notes.
Using sharps you can now play five new notes, which occur between the seven natural notes you already know. This exercise uses all twelve notes which occur within one octave of music. Note that there are no sharps between B and C, or E and F. This is because they are already one semitone apart and there is no room for an extra note between them. Play the following exercise slowly and steadily, making sure you use the correct fingering.