21.   At Paris subway stops and in train stations, transport officials were replacing trash cans with open cardboard cartons out of fears that explosives could be stashed inside.

22.   How then, did he get to sleep in cardboard cartons in Tompkins Square Park as an adult?

23.   Choi told reporters Sunday he had survived on water seepage and by chewing on a cardboard carton.

24.   Next to her, children tapped out a beat on empty cardboard cartons.