Millions are joining RedNote ahead of the TikTok ban. But the app’s default language is Mandarin. “Oh so NOW you’re learning Mandarin,” Duolingo tweeted on Monday.

TikTok U.S. users have been learning Chinese on Duolingo in increasing numbers amid their adoption of a Chinese social app called RedNote ahead of the

Many Americans are joining RedNote, also known as Xiaohongshu, as a potential TikTok ban looms in the US. As they hop from TikTok to RedNote, some of the so-called TikTok refugees are learning Mandarin to bridge the language divide on the Chinese app.

RedNote is a foreign-owned app, and experts warn that it could be attacked by the same law that is now banning TikTok.

Duolingo has seen a surge in U.S. Mandarin learners as TikTok users explore Chinese social app RedNote amid a looming ban.

"First of all, the Chinese are so nice, they're so sweet and so welcoming. They've over here teaching us Mandarin."

Despite the massive popularity of RedNote in the United States and the different corners of the globe, a majority of its users are still mainly speaking Chinese, and this language barrier has Duolingo racking up its numbers.

Can RedNote sustain its rapid rise to success with US users? Even with a TikTok ban and Duolingo boost, it faces plenty of headwinds.

Shanghai-based Xiaohongshu, or RedNote as it is known in English, is a Chinese social media platform growing in popularity as an alternative to TikTok, but with the same security risks.