river system造句

1、The river system is one of the most important ecological system.
河流系统是自然界最重要的生态系统之一。

2、Amazon River system and French Guiana.
分布亚马逊河系统和法属圭亚那。

3、The river system where the alignment passes by is not developed.
线路经过地区的河流水系较不发达。