Word: pledge（noun 、verb）
Source Sentence: They claim Park broke an election pledge to respect previous agreements jointly signed between the South and North, including the Oct. 4 Declaration.
Definition:（1）noun a deposit of personal property as security for a debt
（2）verb promise solemnly and formally
Synonyms:earnest、 token、pawn 、hostage
Chinese:noun 誓约，信物，抵押 verb 抵押，使发誓，保证
Personal Sentence:I pledged that i will earn much money.