自告奋勇

Explanation: Report said that, that. Volunteered as a daunting task. 　　Usage: The main predicate; as predicate, object, adverbial; with a compliment 　　Source: Qing Li Baojia "Bureaucrats" spare the fifty-third back to keep this a lion was only this country; because top advocates traveling, so he volunteered to prefer self-funding ax, called his son went overseas. " 　　Examples: ~ Kind of fishing households, more than fine salt over 50 young hunter, bow with arrows to go looking for Phi. ★ Qu Bo "Snowy Forest" 36 Thesaurus:  bell the cat, volunteer one's services as Mao sui once did, Xitingzunbian, present oneself Antonym Group:  Had nothing to do, indecision, be an onlooker; sit by and watch; watch the fighting from behind the rampart, look on coldly as a bystander, Sit by and watch Not save, Hesitate when decision is needed, No activity Yuzhong, none enthusiasm, apathy, dither, Dread not before, flinch, lack of interest, enthusiasm or concern, sit by, leave sb. in the lurch, boggle