TYPICAL ERROR Violins, trumpets, guitars, recorders. All sorts of instruments are taught by
our instrumental teachers.
CORRECTION Violins, trumpets, guitars, recorders - all sorts of instruments are taught by our instrumental teachers.
EXPLANATION Notice that the subject of the sentence above is a list. This is what is called a scattered subject. Notice how this scattered subject has been gathered together in the subject all sorts. When scattered subjects are brought together in one subject, we use a dash before that single subject.
Move the dash to the correct position.