(LONGMAN2000) system | Definition: 系统 | (IELTS4000) system | Definition: organized structure for arranging or classifying | (NGSL) system | Definition: set of organized, planned ideas that work together | | (ESS4000) ecosystem | Definition: An ecosystem is a group of plants and animals in an area. | Example: →The river’s ecosystem not only includes fish but other insects and plants too. |