Mandarin or 普通话 (Putonghua) is the main language of China. However, pretty much every area in China has its own dialect. In Wuhan, you may also hear people speaking 武汉话 (Wuhanhua).
We use the Chinese renminbi (RMB), which we also call Chinese yen or yuan 元. The measurement of money here is 快 (kuai). However, most people will pay for things through an app (Alipay or Wechat) on their phone, much like Apple Pay or Venmo, so no one ever has 现金 (xian jin), or cash.
A bottle of water costs about two 块, give or take. Anything more than two 块 would seem expensive, though!
The best meal I ate this week was a homemade meal my friend 谢宁(XieNing) made. He made 番茄鸡蛋 (fanqiejidan) and 黄瓜鸡蛋 (huanggua jidan), which are sautéed tomatoes and eggs and sautéed cucumber and eggs, respectively. Having a friend make me a home-cooked meal was such a special treat and it really made me feel cared for and a part of my community--especially because food is such a huge part of Chinese culture. For example, as a way of greeting, people will say: “你吃了吗?” (ni chi le ma?) which means “Have you eaten?” Saying this is a way of showing you care about the other person and their well-being.