undercover
US
UK undercover adj: (agent, policeman: spying) (从事秘密工作的)
SC 卧底的 wò dǐ de
An undercover agent agreed to sell him narcotics.
undercover adj: (operation: secret, clandestine)
SC 秘密的 mì mì de
SC 私下进行的 mì mì de ，sī xià jìn xíng de
The undercover operation was aimed at infiltrating terrorists.
undercover adv: (operation: in secret)
SC 秘密地 mì mì de
SC 在私下进行地 mì mì de ，zài sī xià jìn xíng de
Police went undercover to learn how the bribery scheme worked.