I was heading on a secret mission that made my flesh crawl.我正要执行一项让我心惊肉跳的秘密任务。He was sent on a secret mission approved by the Pentagon.他被派出执行一项由五角大楼批准的秘密任务。He volunteered to embark on a dangerous secret mission into occupied France.他自告奋勇，参加一个危险的秘密任务，潜入被占领的法国。