story: Ed whistled a popular tune as he worked at his desk job. After a while one of his co-workers joined in. The two of them whistled so loud that the whole office heard. Ed and his co-worker were cheered when the song ended. Ed told his co-worker that next week they should perform again!
 selected sentence: Ed whistled a popular tune as he worked at his desk job.
Ed whistled a popular tune while working at his desk >Causes/Enables> One of Ed's co-workers joined in the tune 