Điền từ/cụm từ thích hợp vào những chỗ còn trống trong đoạn văn sau.

American folk music originated with (1) ________ people at a time when the rural population was isolated and music was not (2) ________ spread by radio, records, or music video. It was (3) _______ by oral traditional and is noted for its energy, humor, and emotional impact. The major source of early American folk songs was music from the British Isles, but songs from Africa as songs of the American Indians have significant part in its heritage. Later settler from other countries also contributed songs. In the nineteenth century, composer Steven Foster wrote some of the most enduringly popular of all American songs, (4) _________ soon became part of the folk tradition. Beginning in the 1930s, Woody Guthrie gained great popularity by adapting melodies and lyrics and supplying new ones as well. In the 1950s and 1960s, singer – composers such as Peter Seeger, Bob Dylan, Joan Baez continued this tradition by urban’ folk music. Many of these songs deal (5) ________ important social issue, such as racial integration and the war in Vietnam.