1.   An American official here said American experts were puzzled by the blowup.

2.   Airline accidents today, like the recent American Airlines crash in Queens, can puzzle safety experts.

3.   The statement has puzzled some experts and drew suspicions that the navy officials were withholding some information.

4.   Three weeks into a new age of anthrax, experts puzzled over an unexplained substance found among spores in a letter to Senate Majority Leader Tom Daschle.