Review the item:
If Carlos had known that hail the size of golf balls would fall later that day, he would have __________ his shoulder pads and football helmet instead of his one good suit.

The blank requires the past participle of wear, an irregular verb. Worn is the past participle form.

Verb Simple
Present
Simple
Past
Past
Participle
wear wear(s) wore worn

Wore, the form you chose, is simple past. A simple past verb cannot have auxiliary verbs like would or have. Before you continue, review the rules for irregular verbs.

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