试体会下句中accessory和accomplice的区别:If he helps the felon's preparations, he is an accessory before the act; if he helps the felon to escape punishment once the crime has been committed, he is an accomplice after the fact.如果他帮助罪犯准备,他是事前帮凶; 如果他在罪犯作案后帮助其逃脱惩罚,他是事后帮凶。