The lrm is used to ensure proper text direction in mixed language documents.

左到右标记用于确保混合语言文档中的正确文本方向。

The bidi control characters help manage the direction of text in mixed-language documents.

双向的控制字符有助于管理混合语言文档中的文本方向。

These languages are in addition to the installed language version of the product, and provide additional features to work in a mixed-language environment.

这些语言作为对已安装语言版本的产品的补充，并提供在混合语言环境下使用的附加功能。