foil
The definition for foil is "One that enhances or underscores by contrast." Used in a sentence: The sweet cookie was a perfect foil to the sour lemon sorbet.
heed
The definition for heed is "To pay attention to." Used in a sentence: "Heed my advice," the fortuneteller warned Sebastian when he tried to ignore her prophecy.
inauspicious
The definition for inauspicious is "Not favorable." Used in a sentence: Gary believed the black foreboding sky was an inauspicious sign.
manifest
The definition for manifest is "Obvious." Used in a sentence: James finally made his affection manifest when he handed Jessica a red rose.
redouble
The definition for redouble is "To make twice as great." Used in a sentence: As the sun began to set, Brittany redoubled her effort to find the necklace she had dropped in the field.