排比句是一种修辞手法，指在句子中重复使用同样的语法结构和语言节奏，以强调并增强句子的表现力和感染力。排比句的语言流畅、节奏感强，常用于文学作品、演讲、广告等场合，使文本更加生动、形象、有感染力。

例如，著名演讲家马丁·路德·金的名言：“I have a dream that one day this nation will rise up and live out the true meaning of its creed: 'We hold these truths to be self-evident, that all men are created equal.' I have a dream that one day on the red hills of Georgia, the sons of former slaves and the sons of former slave owners will be able to sit down together at the table of brotherhood. I have a dream that one day even the state of Mississippi, a state sweltering with the heat of injustice, sweltering with the heat of oppression, will be transformed into an oasis of freedom and justice. I have a dream that my four little children will one day live in a nation where they will not be judged by the color of their skin but by the content of their character. I have a dream today.”

在这个例子中，马丁·路德·金运用了多个排比句，以强调他的梦想和希望，增强演讲的感染力和说服力。每个排比句都重复使用了相同的语法结构和语言节奏，如“I have a dream that one day…”和“sweltering with the heat of…”等，使整个演讲具有了强烈的节奏感和感染力，使听众更容易接受和记住其内容。

总之，排比句是一种表达强烈情感和强调语言节奏的修辞手法，常用于文学、演讲、广告等场合，使文本更加生动、形象、有感染力。