CREATE TABLE table_name_27 (opponents_in_the_final VARCHAR, outcome VARCHAR, surface VARCHAR)

Tell me the opponents for runner-up and surface of grass
SELECT opponents_in_the_final FROM table_name_27 WHERE outcome = "runner-up" AND surface = "grass"
SELECT "opponents_in_the_final" FROM "table_name_27" WHERE "grass" = "surface" AND "outcome" = "runner-up"