Gmail, its hugely successful E-mail system, was released to the world in beta (ie, testing) mode and stayed that way for years.

一款获得了巨大成功的电子邮件系统，以测试版的形式发布，并且将这个标签保留了多年。

youdao

Gmail, its hugely successful E-mail system, was released to the world in beta (ie, testing) mode and stayed that way for years.

一款获得了巨大成功的电子邮件系统，以测试版的形式发布，并且将这个标签保留了多年。

youdao