Simple Examples:
* Air-conditioning-unit (air conditioning + unit)
* Breakfast-lunch-dinner (breakfast + lunch + dinner)
* High-speed-rail-network (high speed + rail + network)
* Three-dimensional-modeling-software (three dimensional + modeling + software)
More Complex Examples:
* Early-morning-rush-hour-traffic-jam (early morning + rush hour + traffic jam)
* Second-hand-smoke-induced-health-problems (second hand + smoke + induced + health + problems)
* State-of-the-art-artificial-intelligence-powered-virtual-assistant (state of the art + artificial intelligence + powered + virtual assistant)
* Cross-platform-multi-user-interactive-game-design-software (cross platform + multi user + interactive + game design + software)
Things to note:
* Combined compound words are often very long and complex.
* They are frequently used in technical writing and specialized fields.
* Hyphenation can be used to improve readability, but often these words are written as one long word.
Alternatives:
While grammatically correct, combined compound words are often considered cumbersome and difficult to read. Alternatives include:
* Phrases: Instead of "high-speed-rail-network," use "high-speed rail network."
* Shorter compound words: "Air conditioning unit" is more concise than "air-conditioning-unit."
* Acronyms: "AI" for "artificial intelligence" or "VR" for "virtual reality."
Ultimately, the best approach is to choose the most clear and concise language for your audience.