Table: fa_cup_matches_51
Columns: tie_no
home_team
score
away_team
date

Question: What date was the away team Morecambe?
SQL: SELECT "date" FROM fa_cup_matches_51 WHERE "away_team" = 'morecambe'

Question: What team was the away team when the home team was Grimsby Town?
SQL: SELECT "away_team" FROM fa_cup_matches_51 WHERE "home_team" = 'grimsby town'

Question: What team was the away team when the home team was Hereford United?
SQL: SELECT "away_team" FROM fa_cup_matches_51 WHERE "home_team" = 'hereford united'

Question: What team was the away team when the tie no is 40?
SQL: SELECT "away_team" FROM fa_cup_matches_51 WHERE "tie_no" = '40'