Referred.
The past tense of refer is referred.
The past tense is had.
have in past tense is had
The past tense of have is had.
The past tense of refer is referred.
The past tense of 'spell' is 'spelled'. 'Spelt' is also used in British English.
You spell the past tense of settle like this: Settled
The past tense is traveled.
The past tense is hoorayed.
The past tense is roped.
The past tense is coasted.
The past tense is benefited.