高中 (gāozhōng) is a standard, everyday term used in both formal and informal contexts when discussing education, personal history, or family.
In Conversation: People frequently refer to their 高中 years when sharing memories or talking about their background. For example: “我高中是在北京上的” (Wǒ gāozhōng shì zài Běijīng shàng de) - “I went to high school in Beijing.”
As an Adjective: It is often used to modify other nouns, like 高中生 (gāozhōngshēng) for “high school student” or 高中同学 (gāozhōng tóngxué) for “high school classmate.”
Connotation: The term itself is neutral, but it almost always evokes a sense of intense pressure, hard work, and nostalgia. For those who succeeded in the 高考, it can be a source of pride. For others, it might be remembered as the most stressful period of their lives.