Task: Question Generation
Input (English): Traditional English ale was made solely from fermented malt. The practice of adding hops to produce beer was introduced from the Netherlands in the early 15th century. Alehouses would each brew their own distinctive ale, but independent breweries began to appear in the late 17th century. By the end of the century almost all beer was brewed by commercial breweries.
Output (English): In what century did the first independent breweries appear in England?