The professor explains how to play a specific passage and proposes technical exercises - on finger extensions - to get it. The bow has to be close to the string, without jumping.
About phrasing, it is necessary to build the line. They also work on the vibrato in high pitches and on how to avoid accents where there are none - by changing arm gestures to prevent them.
The student has to study the dotted rhythms, as if they where triplets. The articulation and the rhythm in the left hand are also important. About finger position, it is advisable to remove the tension from the fingers after each note, instead of pushing them backwards.