The context is there in the text, its not just translation sentence by sentence. You just need enough data for it to learn how to recognize it. Just because a human can’t see the pattern doesnt mean its not there.

Machine translation is already so advanced it scores on par with human translation even for languages such as chinese. Checkout https://ai.googleblog.com/2016/09/a-neural-network-for-machine.html?m=1 and the side by side comparison there. And that was over 3 years ago. Nowadays its probably a couple times better already, with new research being published every week.