Review the item:
Mauricio would have _________ the seven-foot wave into shore if a huge shark had not been patrolling the waters underneath the surfboard, hungry for a dangling arm or leg.

The blank requires the past participle of ride, an irregular verb. Ridden is the past participle form.

Verb Simple
Present
Simple
Past
Past
Participle
ride ride(s) rode ridden

Rode, the form you chose, is the simple past. You cannot use the simple past if you have auxiliary verbs like would and have. Before you continue, review the rules for irregular verbs.

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