The first movement adopts the speed of Allegro, C major, 4/4 time and sonata form. At the beginning, the theme of the main part is quite clear, while the theme of the auxiliary part is simple and happy. The contrast between them is very clear. The expansion part is written by broken chord and scale phrases.
the structural analysis of the first movement is as follows: (musical notation is abbreviated)
Presentation section: section 1-28
Main section: section 1-12, paragraph structure. The first four bars give people a light and transparent feeling in C major. Section 5-8 is a 4-bar scale insertion structure. From the ninth bar, the music goes to the dominant key in C major and G major, and ends with the main chord in the 12th bar. The theme of the main part gives people a clear, open, beautiful and elegant feeling, which embodies Mozart's simple and skillful creative skills.
connecting part: the 13th section is played in the bass with continuous sixteenth notes in G major, which seems to be the introduction to the transition to the minor part, so that the theme of the minor part can enter smoothly.
sub-part: from the 14th section to the 26th section, the theme of the sub-part is carried out in G major, and the tone is just the opposite of the theme of the main part, but the rhythm is tightened, so we can see the conciseness of Mozart's material application. Section 18-21 is written in arpeggios, which is also a form of parenthesis. harmonic progression of T6-S-D Ⅶ 6-DT Ⅲ-TS Ⅶ 6-S Ⅱ-D6-T has a great personality. Section 22-23 appeared in the second half of the minor part in A minor, and it was transferred from section 24 to G major. The materials used were the motivation of the beginning of the minor part. The 26th bar ends with a full stop on the main chord in G major. The material of the whole auxiliary part is the change and application of the main part, which has the characteristics of simplicity and happiness and forms a sharp contrast with the main part.
Ending part: Section 26-28, which ends in the form of D7-T with the repetitive sound pattern structure in G major in different sound regions.
development section: section 29-41. Along the end of the presentation part, with the same phonetic structure, it is transferred to the G minor of the same name in G major at the end part, followed by a series of scale phrases and the application of broken chord. In the first half of bar 31, the scale on the main chord in G minor is played, and in the second half, the scale in D minor is played, and the bass and treble alternately echo. Sections 33 and 34 are carried out in D minor by using D7-T with homophone structure and different sound areas. In the 35th section, there are high-low scale phrases in D minor, and in the 36th section, there are high-low scale phrases in A melody minor. From section 37 to section 4, A minor and D minor are used to form a one-stop structure through alternating scale phrases of high and low voices. In the 41st section, D7 with definite tonality appeared in the parallel key F major in D minor, which prepared for the appearance of the reproduction department. The whole unfolding part is in sharp contrast with the presenting part in terms of mode, tonality and materials, and the ups and downs of scale phrases give a strong impetus to the development of music.
reproduction department: section 42-73.
main part: section 42-57, which is different from the presentation part in tonality. It reproduces the theme in the subordinate key F major of the main key C major in the presentation part, reflecting the display of Mozart's genius, and expands four sections to let the left hand flow in the bass part in order to return to the subordinate key G major of the main key C major.
Connecting part: Section 58, the obvious change is that the tonality returns from G major to C major, and the material is the same as that of harmonic progression and presentation part.
sub-section: in section 59-71, the tonality returns from G major to C major, and harmonic progression T6-S-D ⅶ 6-DT Ⅲ-TS ⅵ 6-S Ⅱ-D6-T is still distinctive. The second half of the theme of the sub-part is slightly changed, and a minus seven chord is used in the 68th bar. Section 69 becomes a scale form, and the application of this scale conversion form reflects the uniqueness of Mozart's music creation techniques. Finally, it still ends with the main chord.
conclusion: sections 71-73. The writing is basically the same as that of the presentation part, except that the tonality returns from G major to C major, and it is completely terminated.
this piece of music has a smooth melody and a clear structure, and it sounds exciting. It can be seen that Mozart's music embodies the most perfect style in the classical period and the ideal of pure music.
Mozart is not a cheerful and lively person or an optimist, but he is not a melancholy person or a pessimist. But in his works, there is no dull Ping Ye, and there is no esoteric Jedi. He neither allows himself to do things cheaply, nor allows himself to lose rhythm. He just shows the truth of everything within certain limits. This is where his music is wonderful, sweet and moving.
Mozart's music is different from Bach's gospel music and Beethoven's heroic epic music. His music does not preach theory, let alone express himself. He didn't mean to say anything, he just sang, just made a sound. Therefore, he does not impose anything on the audience, nor does he ask them to make decisions or show their attitude, but makes them feel free. This reflects his realistic spirit of freedom, and is also starting his own path.
In Mozart's music, spirit and form are completely unified, and he may be able to say things that cannot be spoken but can only be spoken by sound.