system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How does China artificially keep its currency cheap?

I've tried reading around and googling but I cant seem to find a simple enough explanation for the not so financially savvy me. So, if anyone of you awesome people can help me out here. **How does China artifically keep its currency cheap? What do they have to do in order for this to happen? Any long term or short term consuquences?**
gpt
Instead of exchanging the USD they've earned into yuan (thus resulting in a surplus of USD in circulation in international currency market and short supply of yuan, in other words, devalued USD and higher value in yuan), they buy US treasury bonds, which is in USD denominations, it's not affected by the value of yuan. That way the supply of yuan circulating in the international currency market will never be low.