Review the item:
Because Henry enjoyed impressing his girlfriend Gloria, he __________ for the expensive dinner with his brand new credit card; he would worry about the shocking statement when it arrived in the mail next month.

The blank requires the simple past of pay, an irregular verb. Paid is the simple past form.

Verb Simple
Present
Simple
Past
Past
Participle
pay pay(s) paid paid

Payed, the form you chose, is a spelling error. Before you continue, review the rules for irregular verbs.

Try again to escape Grammar Hell!