Here is the sentence:
The hungry shark swam beneath the unsuspecting surfer and began to position itself for an attack. Then the fish noticed the hot pink toenail polish on the foot that dangled over the surfboard and losed its appetite.
The third verb, losed, is the problem. As you know, this sentence requires the simple past of lose, an irregular verb. Lost is the correct form; losed is a spelling error.
|Verb||Simple Present||Simple Past||Past Participle|