Task: Question Answering
Input (English): Context: I checked my rig , sat in my seat and took the oars . Time to focus . Big water lay waiting downstream , a string of serious and reverent names like Horn Creek , Granite , Hermit and Crystal . As our group pushed off and my boat swung out into the Bright Angel riffles , I started to sing Do n't Fence Me In , and , you know , I think I never sounder better . 
Question: What may be the reason why they were singing so good ?
Output (English): Because they were relaxed .