I studied abroad in Shanghai, China for about 4 months and my experience was incredible. I did not speak any Mandarin when I decided to go but i knew the best way to learn the language was by actually being exposed to it and practicing it everyday. It was a little difficult at the beggining but the more I practiced the more confident I became when talking to taxi drivers and locals.
Overall, I found Chinese people to be very welcoming of foreigners and if you travel to the rural areas of China, dont be surprised if you are asked to take a picture with them, as they most likely have not see a foreigner before or barely have had interaction with any. As far as pollution, there days that it was so foggy due to it, during these days I tried not going out as much or engaging in outdoor activities. As time passed by I grew accostumed to checking the level of pollution almost every day and having a mask handy to use when needed. This did not become an impediment for me to have a great time, although I was always conscious of the the threats of inhaling polluted air.
Transportation was amazing, I could easily move around to any part of China via trains or buses. Of course, always doing my research on which way was the most convenient/cheapest/fastest. Food related, it is always good to befriend locals, as they will show you the best spots for food and how to move around. There are plenty of options for food around in Shanghai, and I found variety in Beijing too. Food is cheap but that also depends on where you go, if you choose a more western restaurant the prices will tend to be high and almost compare to the prices in the U.S.
The nighlife in China is also great; there are plenty of bars and clubs to go to any day of the week. It is a plus if you know a chinese promoter as they will get you in for free and you will have drinks fo free all night. In addition, I felt very safe while walking around in China at any time of the day. Never did me or my friends felt threathened in any way. Although, becareful when you go out to clubs or major tourist points, as pickpocketing is very popular. I, however, never encountered a situation where it happened to me.
On the not too bright side, you will find chinese people sometimes cutting lines in front of you if you dont move too fast, or happen to be distracted. Coming from the U.S. where waiting for your turn is usually not a problem, it can definitely be bothersome. In addition, Chinese people can be very curious and ask questions that you are not usually accostumed to. For example they will ask you how much you make and other impertinent questions.
Before leaving to China, ensure to download a VPN or Virtual Private Network as it will allow you to check your facebook or gmail along with other pages that are blocked in China. I would strongly recommend investing in a good router so you dont spend time complaining on how bad the connection is. Although, sometimes slow I did not find any major issues connecting and speaking to my family and friends back in the U.S.
China is definitely an interesting place that has great things to offer; food, beautiful places to visit and the opportunity to engage and learn from a total different culture and traditions. I am very glad I visited China and would definitely recommended it for anyone to experience it.