Compare two of the set works for A level, focussing on instrumentation and structure.

Answer depends on set works. Look at instrumentation for each - compare to each other, and to standard orchestrations of the time. References to how orchestras developed, or in case of modern music how ensembles and standardisation of ensembles grew. With structure, refer to the structure of each piece, describing how the piece is laid out in detail. Describe any similarities or differences, and refer to typicalities or abnormalities of that piece within the era or genre that it was used.

To revise this answer, it depends on the set works asked. This is a generic frame of reference, a skeleton on how to write this particular question, and tutees would work on details of the set works before attempting this question.