PHRASAL VERB 自告奋勇;主动提供(信息) If someone comes forward, they offer to do something or to give some information in response to a request for help. 自告奋勇;主动提供(信息)
A vital witness came forward to say that she saw Tanner wearing the boots. [VERBPREP.]
一位非常重要的证人站出来说她看见坦纳穿着那双靴子。
SYN volunteer, step forward, present yourself, offer your services