Definition: In this task, you're given a four sentences of story written in natural language. Your job is to complete end part of the story by predicting appropriate last sentence which is coherent with the given sentences.
Input: Sentence1: Tone-deaf Melanie and her talented pal tried out for choir at school. Sentence2: Melanie only mouthed the words, while her friend sang aloud. Sentence3: The music teacher was impressed and accepted them into the choir. Sentence4: The teacher gave Melanie and her pal a duet to sing at the concert.

Her friend got sick, so Melanie had to sing by herself.