Mozart Sonata in Bflat Major K333, I: m23-38

This excerpt consists of a parallel double period of four symmetric, four-measure phrases. In addition, all though the work is in B flat major, the piece has by this time modulated to the dominant F major key. The two smaller eight-measure periods are parallel, for each of their antecedent, four-measure phrases are the same--they both end in imperfect authentic cadences. The consequent of each of the two eight-measure periods begins with a c sharp to a d, but that is where the two consequent phrases diverge in their similarity. The ending of the first consequent phrase runs into the beginning of the second period, thus forming a very strong PAC that moves right along melodically. The second consequent phrase concludes less dramatically and reaches a PAC in the left hand by the second part of the last beat of its fourth measure (m 38). The music then is marked by fp and new material, so the less emphasized nature of the concluding PAC presents a musical opportunity for graduation into new material.