>Also it turned out that learning to read when you already know how to speak (and can read other languages, I suppose) is actually quite easy. By now I can read novels etc. in Spanish without too much effort.
Spanish is likely an outlier here as it is spelled phonetically. French is more difficult, but not terribly so. However languages that are written with a different script, or in a completely different system like Chinese offer a much larger hurdle. Chinese literacy, in particular, is orders of magnitude harder.
I'll second that - in addition to my home university studies, I spent a year on exchange in Japan where pretty much all I did was study kanji and vocab - because we had at test on the 1942 kanji called necessary.
As it turns out I aced the test, and all that study is a big part of why I'm comfortable with reading a newspaper. Still have to look things up from time to time, but for the most part I know how to read the word even if I don't know the exact meaning. In that sense, I agree with the blogger that rote memorisation is key - and not just words, but often whole sentences as that gives context.
As for Spanish, it's cognate in some areas with English, so that's at least one part of why English natives are able to learn latin languages at a faster click than other languages. The blogger will find it easier to learn Japanese.
Spanish is likely an outlier here as it is spelled phonetically. French is more difficult, but not terribly so. However languages that are written with a different script, or in a completely different system like Chinese offer a much larger hurdle. Chinese literacy, in particular, is orders of magnitude harder.