水系的英文：
water system

参考例句：

During the Pleistocene Ice Age, the ancient drainage systems were almost completely rearranged by glaciation
在更新世冰期，古水系常被冰川作用完全改造。

The endless variations of drainage pattern make descriptive characteristics difficult
水系型式的无限变化给描述特征带来了困难。

Drainage was to the north and individual channels bifurcate in that direction
整个水系向北排水，各个河道朝该方向分叉。

The difference is mainly in the tone not in the drainage pattern or landform
所不同的主要在色调，而不在于水系型式或地形。

The plants using a closed-circuit water system will usually require some means of treatment of excess water
使用闭合循环水系的工厂，通常需要以某些方法处理过剩的水。

water是什么意思：
n. 水；雨水；海水；海域
v. 给…浇水；供以水；加水；流泪；流口水

In smooth water
进入顺境

Is the water on or off?
自来水龙头开着还是关着？

Water Skiing is a surface water sport.
滑水是一项水面运动。

Please fetch some water to water the flowers.
请你去弄点水来浇花。

Water will flow from their buckets; their seed will have abundant water.
水会从他们的桶里流出，而种子会获得充足的水源。

system是什么意思：
n. 体系，系统；设备；制度；方法；身体；次序

Is the system unstable?
是系统不稳定吗？

It was not a perfect system.
它不是一个完美的系统。

This is a sexpartite system.
这是一个由六部分组成的系统。

Anatomically, the nervous system is divided into the central nervous system and the peripheral nervous system.
解剖学上把神经组织分为中枢神经系统和周围神经系统。

disaccord between the economic system and political system
经济体制与政治体系间的不协调