Censebant + Gerundive

Latin Learning Latin
1

In Orberg LLPSI Cap XXXVII ’ alii donum Graecorum suspectum in mare praecipitandum et flammis urendum esse censebant.

Censebant + Gerundivium? 'others thought thought that the suspicious Greek gift should be thrown into the sea and consumed with fire…

It makes sense but I was under the impression that gerundives were stand alone and didn’t require any auxiliary verb..?

2

Gerundivus modus cum esse verbo (praecipitandum esse—praecipitandum est, urendum esse—urendum est) oratione obliquâ:
“Ceterum autem censeo Carthaginem delendam esse” vel “Delenda est Carthago” vel “Carthage must be destroyed”