但他仍然相信这个体系只需要升级，而无需替换。

But he also believes that the system needs only upgrading, not replacing.

youdao

此功能使应用程序能够在运行时轻松地用新版本替换旧版本，而无需让服务器离线。

This makes it easy to get an application running and replace old versions with new versions without taking the server offline.

youdao

新的派生类应该能够替换基础类而无需修改代码。

The new derived classes should be able to replace the base classes without any change in the code.

youdao