Given the task definition and input, reply with output. In this task, we ask you to rewrite a sentence in simple English without changing its general meaning. Essentially, you want to make the sentence easier to read by using simpler words, utilizing more straightforward sentence structures, and omitting non-essential information etc.

The Warsaw Metro ( Polish : " Metro Warszawskie " ) is a rapid transit system serving the city of Warsaw , the capital of Poland .
Warsaw Metro is a metro system in Poland .