How to take care of ducklings<br>Find a brooding box. After ducklings have hatched from their shells and spent about 24 hours getting used to their new surroundings, they're ready to move to a brooder. A plastic storage container, sturdy cardboard box, or large glass aquarium can all work for this purpose.
weak cardboard is better than sturdy
it says to use sturdy cardboard, not weak. 
( z1 have-degree :ARG1 ( z2 cardboard :ARG1-of ( z3 weak ) ) :ARG2 ( z4 good :ARG1 z2 ) :ARG3 ( z5 more ) :ARG4 ( z6 sturdy ) )