CREATE TABLE table_73940 ("Year" FLOAT, "Championship" CLOB, "Surface" CLOB, "Partner" CLOB, "Opponents in final" CLOB, "Score in final" CLOB)

What was the surface when he played with John Alexander?
SELECT "Surface" FROM table_73940 WHERE "Partner" = 'John Alexander'
SELECT "Surface" FROM "table_73940" WHERE "Partner" = 'John Alexander'