The bridges were necessary because where the Canadians were crossing the Canal du Nord was flooded and the only locations that had no flooding were being guarded by the German defences .
DET NOUN AUX ADJ SCONJ ADV DET PROPN AUX VERB DET PROPN PROPN PROPN AUX VERB CCONJ DET ADJ NOUN DET VERB DET NOUN AUX AUX VERB ADP DET ADJ NOUN .