The F major scale starts and ends on the note F, and it contains a Bb note instead of a B note. Play the F major scale below and listen for the Do Re Mi Fa So La Ti Do sound.
Songs that use notes from the F major scale are in the key of F major and hence contain the note Bb. The key signature containing the note Bb which was introduced on page 26 is the key signature of F major. Go back through the book and look for other examples of the key of F major.
Here is a lively folk melody in the key of F major. You will need to breathe where the rest occurs at the end of bar 4. Make a habit of looking through tunes to find the best places to breathe before you begin playing.