敬语和平语是日语中非常重要的语言表达方式，它们之间有很大的区别。

首先，敬语是一种表示尊敬和礼貌的语言表达方式。在日语中，敬语有三种：尊敬语、謙譲語和丁寧語。尊敬语用于对别人表示尊敬，例如对长辈、上级、客户等；謙譲語则是用于表达自己的谦逊和尊重，例如在自我介绍、请求、道歉等场合；丁寧語则是一种礼貌用语，用于日常交流中的表达。

相比之下，平语则是一种普通的语言表达方式，它不涉及到尊重或者礼貌等方面，适用于日常生活中的交流。平语也有时态、语气、语法等方面的变化，但不会像敬语那样需要特别的语言表达。

总的来说，敬语和平语之间的区别在于敬语用于特定的场合，表达尊重和礼貌，而平语则是日常交流中的常用表达方式。在日语中，正确使用敬语和平语是非常重要的，因为它们涉及到对他人的尊重和礼貌，也体现了一个人的修养和社交能力。

In Japanese, there is a significant difference between keigo (honorific language) and heigo (plain language). Keigo is a form of language used to show respect and politeness. There are three types of keigo: sonkeigo (respectful language), kenjougo (humble language), and teineigo (polite language). Sonkeigo is used to show respect to others, such as elders, superiors, and clients. Kenjougo is used to express one's humility and respect, such as in self-introductions, requests, and apologies. Teineigo is a polite form of language used in daily communication.

In contrast, heigo is a plain form of language used in everyday communication. It does not involve respect or politeness and is suitable for casual conversations. Heigo also has variations in tense, mood, and grammar, but it does not require special language expressions like keigo.

In conclusion, keigo and heigo differ in that keigo is used in specific situations to express respect and politeness, while heigo is a common form of language used in daily communication. In Japanese, using keigo and heigo correctly is essential as they involve respect, politeness, and reflect one's manners and social skills.