1. The wars, ________________, and technology advancement created a big impact to the sounds made by different musicians.

2. In the era of Nazi, many musicians migrated to the United States because _______________ had banned their works.

3. The ____________________ shifted from the church and nobility to the American colleges and universities.

4. Bela Bartok, Igor Stravinsky and ________________ migrated to the United States for experiencing unpleasant treatment.

5. The _______________________ eased the composing and disseminating process among composers and music producers.​