系统升级的英文：
system upgrade

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

upgrade是什么意思：
n. 上坡，上升；升级
v. 改良，升级；晋升，提升

Companies need to upgrade servers.
公司需要对服务器升级。

He was upgraded to security guard.
他被擢升为保安。

The first is upgrading our infrastructure.
首先，我们要改善我们的基础设施。

You must upgrade to Premium to burn this file.
您必须升级到精品版才能刻录此文件。

The power plant received a new upgrade.
那个电厂进行了一次升级改造。