1.   Select the "expressions" keyword.

2.   In the right pane, select the topic title Avoid archaic words and expressions.

3.   Right-click the topic and select Index from the shortcut menu.

4.   Select the secondary keyword archaic.

5.   In the right pane, select the topic title Avoid archaic words and expressions.

6.   Right-click the topic and select Index from the shortcut menu. The topic has been associated with the both the primary and secondary keywords.