Passive voice: "historic cities and buildings" is used here in the passive voice (to be preserved), demonstrating the candidate's ability to flexibly use the passive voice to emphasize the recipient of the action rather than the doer, increasing language diversity and formality.
Comparative form: "more on modernizing cities" uses the comparative form (more on), showing that the candidate can accurately use comparatives to express priority or importance differences between things, which is a common and important advanced grammar point in IELTS speaking.
Subjunctive mood: "might be more appropriately shared" uses the subjunctive mood (might be shared), showing the candidate's ability to use appropriate moods in hypothetical or possible situations, a common advanced grammar structure in high-scoring IELTS answers.