This variation is one of many that develop your control while playing mixed bowings.
Here the mixed bowings are four notes spiccato and two notes slurred. As with all such bowing patterns that mix slurs with détaché/sautillé/spiccato, it is important that the slurs use a small amount of bow so that both the separate notes and the slurs work in the same place in the bow. This is usually the balance point or the middle of the bow. Saving bow in the slurs is particularly important when the slur crosses strings as in bar 1 or 6, because string crossing can use a lot of bow.
Practice the bowing on open strings and aim for small strokes with high friction.
We find many variants of this bowing in the repertoire. For example two notes slurred and two notes separate in the 1st movement of the Mozart A Major concerto. In the Mozart the tempo is faster (crochet =120/126) so the stroke used there for the separate notes is a brush stroke rather than a standard spiccato stroke but the principles of bow division are the same.
To develop control:
– Keep the bow in the string at the end of the slur so you start the next spiccato note from the string
– Keep the bow close to the strings. Using the side of the hair allows us to minimise the bounce of the spiccato and to easily put the bow back on the string to play the slur.
– Think about your fingering. Ševčík tends to suggest only a few fingerings and while this variation can be played all in 1st position the larger number of string crosses makes this a greater challenge for the bow. For performance you can move into positions to reduce the number of string crosses. Also think about when to use open strings or 4th fingers so that each two-note unit is on the same string wherever possible.
As always, work on your phrasing and musical line. Here we have a classic short, short, long phrasing structure, that is bars 1-4 are a short phrasing unit of 4 bars, bars 5-8 are another short 4-bar unit and then there is a long phrase of 8 bars from bars 9-16. Start bar 9 softer and allow a crescendo as each two bar phrase rises until the phrasing off at the end of bar 16.