Sentential period

A sentential period is a kind of grammatical theme defined and described by Richards.¹ It can be split up into 2 phrases: the presentation and the consequent.

Note that the repetition of the basic idea, A', must differ from the basic idea itself.

The 2nd A must be more similar to the first A than A' is. This makes it feel like a period.

This form type is not commonly used in film music, though there are some prominent examples (below).²

Examples

The Pink Panther main theme

Raiders of the Lost Ark main theme

The Informer main theme