user: Question: What is the largest average for the episode with 1.97 million Hong Kong viewers?
Columns: ['Rank', 'English title', 'Chinese title', 'Average', 'Peak', 'Premiere', 'Finale', 'HK viewers']
Types: ['real', 'text', 'text', 'real', 'real', 'real', 'real', 'text']
Sample row: [1.0, "Can't Buy Me Love", '公主嫁到', 34.0, 45.0, 33.0, 35.0, '2.15 million']
SQL:

assistant: SELECT MAX("Average") FROM "Table" WHERE "HK viewers" = '1.97 million';