Answer:

striven

Answer	Crossword Clue
STRIVEN	Endeavored
STRIVEN	Tried hard
STRIVEN	Attempted

STRIVEN	Tried hard.
STRIVEN	Had made great efforts.
STRIVEN	Endeavored.
STRIVEN	Labored hard.
STRIVEN	Tried
STRIVEN	Anagram for inverts
STRIVEN	Struggled
STRIVEN	"I have ... to be Thine . . . ": Melville

STRIVEN	Made an effort
STRIVEN	Exerted oneself
STRIVEN	"Other sea-cities have faltered and .. ...": Doolittle
STRIVEN	Gone to great lengths