The first movement starts with motivation, the second movement consists of a long and lyrical theme, the third movement links the motivation of the first movement with the same four-note rhythm, and the emotional tone of the fourth movement is more positive, because the music moves up and the instrument is changed to trumpet.

Demonstration repertoire: Tchaikovsky's first piano concerto begins with three movements, using the same motivation as Beethoven's fifth symphony with four notes.

The piano plays chords, and then the violin plays themes. At this time, the piano will still play chords as accompaniment to echo the violin. Then the roles of piano and violin are exchanged, the piano plays the theme, and the strings are accompanied by plucking.

Second, the motivation and theme:

1, the theme is simply what you want to express, ideas, feelings, etc.

2. Motivation is the rhythmic appearance of any series of sounds, which is called motivation. Motivation consists of characteristic tones and rhythms with at least one stress. It is the germ of theme or music development, and also the most representative small unit of music theme, which has certain independent performance significance.

Extended data:

1. Motivation is the most recognizable unit structure in music, which can be melody or rhythm. If music is compared to a train, the motivation is to add flowers repeatedly in each carriage, thus forming a complete train to go fast.

2. Theme is a concept borrowed from literature and has little to do with music. Not all music works will have themes, and it can be considered that there are, but generally there will be no more. Music titles in a certain period (such as The Romantic Period) can imply or indicate the theme of music, while music in movies is often easy to identify the theme and give it the so-called theme.