而对于后者则要求应用程序功能完备，易使用等特点。
As for the latter requirement applications fully functional and easy to use, and other characteristics.
而对于后者则要求应用程序功能完备，有友好的用户界面，易使用操作等特点。
For the later, however, it requires characteristics of self-contained function of application and having friendly customer interface and easily using operation, and so on.
火狐的雷鸟是乌邦图上默认的电子邮件客户端。他很容易使用安装，有许多先进的特点并允许轻松定制。
Mozilla Thunderbird is the default email client in Ubuntu. It is easy to use and setup, has many advanced features and allows for easy customisation.
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