他们在礼拜仪式上演唱了几首古老的赞美诗。

They sang several old ___chorales during the worship service.

教堂唱诗班演唱的这首赞美诗改编自巴赫的一首四声部合唱曲。

The hymn sung by the church choir was adapted from one of Bach's four-part ___chorales.