"Sometimes" is a 1975 song written by Bill Anderson, and performed by Bill Anderson and Mary Lou Turner.
Anderson wrote the song while riding on a bus in England.
Reading a review of Shampoo, he noticed a section detailing a scene where a character's response when asked if they are married is "sometimes".
Anderson decided this would be an excellent setup for a duet, jotting down the first draft of the lyrics on the magazine the review was in.
[1] "Sometimes" went to number one on the country chart, where it stayed for a single week and spent a total of eleven weeks on the chart.