To turn a previously altered note in the bar into natural, you set the symbol of natural afore the target note. This symbol annuls double alterations (double sharp and double flat) too, but for a major clearness you usually make use of the double natural as well.
Graphically, both symbols appear as follows:
natural
double natural
Examples of temporary alterations:
Examples of double alterations:
When you wish to annul the effect of a single alteration in a doubly altered sound you use to add a natural too:
In case the temporary alteration is set afore a note joined with a value tie to another note set in the following bar, the value of the alteration lasts only for the value of both tied notes.
When the two notes from the previous example are joined trough a portamento tie, the second tie sound must owe the symbol of natural:
When the value tie is between two altered notes in two different bars, of which the first one is at the end of the line, it is necessary that even the second note has the symbol of alteration:
