Which word part is the prefix in convenient? con- -ent veni- co-

What happens once in a minute twice in a moment and never in a thousand years?

Fill in the blanks mommy told the kids, who promised they up their rooms by lunch, that they would go to the park. a would cleanb cleanedc have cleaned

Give an example of one of the choices from the question above. explain what makes your example fit into this classification. use complete sentences, proper grammar, spelling and capitalization.