How to Use "undercover" with Example Sentences

1. The killing involved 27 undercover agents travelling on forged passports .

2. Airport screeners still fail undercover tests of their ability to spot concealed weapons .

3. Undercover informants can be more useful to the groups they monitor than to their paymasters .

4. The operation followed months of undercover police work that gathered evidence of an extraordinarily lucrative empire .

5. Key messages to staff should never go undercover , even if one boss had to don a disguise to find this out .