What does 发誓 (fā shì) mean in English?

Card 517HSK 2010 Level 6517/2512
CARD517
PROGRESS21%
发誓
發髮
fā shì
to vow; to pledge; to swear

Reveal: Click/Space/Enter/↑↓/w/s/j/kNavigate: ←→/h/l/a/d