I am currently learning Mandarin (in Pinyin, Poo-toong-hwah).The script (wuhn-dzuh), in particular, is very fascinating, its history, ideograms, phonetics, etc.
But, on slightly different tack, I thought I would just quote from the (2018) textbook.
''Chinese people don't have O negative blood, so Chinese hospitals do not store it.''

Basically, if anything happens to you in mainland China you have got to get to (your) Embassy for help, then you have to get yourself airlifted out. What is also interesting is that the book specifically states, that you must try to take your own sterile needles into the country, because it actually states you can't guarantee the needles you get there will be sterilised!
Of course, you would't even get your needles into the country in the first place, (and might get arrested for even trying). So what you have to do if you are staying in mainland China is to fly straight back home.
I am a little bit cautious about what the book is saying here. Because I sense the book has a Taiwanese slant to it, meaning it has a US bias to it. That is no criticism and I am not questioning their advice, but I cannot think mainland China is so lacking in this respect.

From my experiences of travel, taking your own sterile need seems to be basic advise for developing countries.

I've never been to China, so can't really comment on that aspect.

But as regards learning Mandarin... Way back in the 90s we had started using China for lots of our body tooling. There was a massive drive from the higher management for the engineering staff to learn Mandarin. I never partook in the learning for various reasons, but several of my colleagues did. A few of them moved out to China before MG Rover went bump. I can't remember the name of the company we employed to do the language training, but by all accounts, they were very good.

I salute you, Mr.H, learning languages is rarely easy, but it keeps the old grey matter engaged.

Interesting what you both say. Probably sterile needles would be a tricky thing to take, certainly on a plane. The tap water in PRC definitely is undrinkable, and mustn't be. I saw a recent vid. where the guy was eating baked scorpions on a stick, a bit like a kebab. And then there are the sea slugs, quite a delicacy apparently. Pass.
On the business front, the key word is guanxi (gwahn-shee) meaning relationships. Fair enough, you've got to have trust between people before you even consider a contract because what's the point in having a contract with a crook? That said, a good contract, well drawn between people that trust one another (who wants an accountant who is only reasonably accurate?) helps to iron out any misunderstanding the two parties simply don't have the time to discuss fully when first they do business.
But the mainland Chinese have raised this to a whole new art form. The books specially say you MUST bring gifts (liwu-lee-woo) to your Chinese business contact but you must NOT bribe them by giving them too much. How you manage this somewhat Delphic model of perfection is anyone's guess.
And then we have come to the ticklish subject of spying. I was only reading yesterday in Australia news how a businessman was approached by two individuals who said they wanted some business information, and could he also collect some data on official sites of the Australian government and for which he was handsomely paid. He is now being done for espionage related offences. A cynic would said, well, the PRC has form in this area, and they will either buy the info or steal it. That is, after all, how they built a mighty world class navy from only a few junk boats 30 years ago by illegally obtaining (through the late Chi Mak) US Navy secrets on nuclear subs.

I don't think the JLR tie-up with China went very well, Mr.H. 'Knock-off' copies are a real problem. I saw yesterday a pretty good copy of the current Defender. I bet it comes in at below half the JLR price.

The documentary (BBC I think) about the MG Rover team negotiating with the Chinese is worth seeing if you have the time.

The 'knock-off' copies of JLR is a v. interesting point. Exports would certainly highlight the issue. But we often forget that the PRC is still to a large extent a closed economy so dummy Jags and Rovers could be made for internal consumption and we would be none the wiser.
You have huge areas of this vast country where no one outside really has a clue what is going on. Western cars and technology are highly prized and they must have swooned at the sight of JLR products (they don't like US cars). We are going to look for this documentary. Sounds fascinating.

There are some droll features of Chinese which provoke (in me at least) a bit of laugh.
The word for sand is SHA (first tone). But a Shafa (double first tone) means a sofa. What is the link between the two - sand and a sofa? Errrmm. Get it?. Both are soft, you sink into.
Buy and sell? No probs. Buy is mai (third tone) and sell is mai (fourth tone). The way these words are pronounced you can say it like when you buy be slow and cautious, third tone, but when you sell you say it quick like you want a quick sale. So how do you say business? easy peasy. Mai, Mai - the process of buying and selling.
Fa (third tone) means method, law, way. The radical ideograph (on the left) shows a river or water. So what's the connection? Well, in ancient China the cities were built on rivers, so that this became the standard practice, the law, if you will.
ZI (pronounced dzuh, fourth tone) means character. This is what's called a pictophonetic compound. The Chinese character (hanzi) comprises the roof radical on the top and zi, child, underneath. Why? Children were supposed to remain at home practising their characters every day, and learning new ones (shengzi).
A curious feature I stumbled on in a pinyin dictionary was the phrase - Gongtong fuyu. Now, this basically means common prosperity. It is the slogan of the CCP. But, unless I'm being very stupid (always possible) I think they have in recent years changed the meaning of this. The old meaning of the phrase was marxist 'the State or People own everything jointly.' But that is not what it means now. It now means "common prosperity we all share in.' And I can prove this because the tones of the two phrases (which is meaning in Chinese) are different. Its really a huge revolution. The party has changed the meaning, they have retreated from rigid marxism to a sort of market socialism. Like Orwell said, 'The Party is in control, the Party has changed reality.'

Sounds far too complicated for me, Mr. H. I had a cousin who was a linguist. She fluently spoke about 8 languages. Whether they were genuinely different or related languages I couldn't say. But I do remember her telling me when I was still at school that the only way to learn a language was to go and live amongst the people.

When I worked as a consultant/lecturer/trainer I often found myself in countries where I had no idea of the language, but English is pretty universal and I always got by. But whilst in Munich I met a Scotsman who spoke fluent German. He had moved out there 6 years earlier with no idea of the language. I had to admire him.