[retroflexzy]

Right. I think I would file all of that under the "hard to translate" category.

Now, let me clarify upfront that my minor (technically a "joint-degree", but effectively a minor) is in Linguistics, so this may get wordy and technical.

What you are mostly describing is a not a restriction of the language itself, but of social conventions. You can certainly say "いいえ、できません". While it is true that Japanese has a relatively substantial honorific structure when compared to English, there are other languages with even richer systems, such as Malay.

One thing that makes Japanese stand out amongst the ones you have listed is the fact that it is a language isolate, meaning there are no other languages that are "linguistically related". (While technically in the Japonic family, there is some controversy around the categorization of Japanese dialects, which muddies the family categorization as well). Korean is another isolate, and, as far as I know, the only language that is remotely like Japanese in terms of grammar and morphology. German, Dutch and Spanish all belong in the Indo-European family, and there are some obvious structural similarities. Mandarin Chinese is certainly not Indo-European, but it also lacks a non-trivial inflection system, and has a basic word order that is not unlike Germanic languages.

Japanese, on the other hand, does not share this trait. Consequently, there are certain grammar constructs in English that are essentially impossible to transform into Japanese; it takes a speaker sufficient in both to first completely comprehend an utterance and then re-express it. Add to this the many subtle semantic differences in words, and it's not surprising that you will get a lot of "that's hard to say"s. However, this doesn't mean that something is untranslatable. Speaking from experience, us polyglots do occasionally use it as an excuse that more precisely means "the exchange which must take place for me to extract more context out of you to effectively perform your request is something I don't want to spend energy on at the moment." ;)

[tel]

I'm curious about the origins of language in East Asia then. I was always under the impression that Chinese dialects heavily influenced both Korean and Japanese (and visa versa) so I'm a little confused by considering both of those to be isolates.

I know the word order is vastly different and the honorific system obscures the language, but what about more fundamental tendencies of Mandarin such as the heavy dependency on chronology or the kind of general sounds of the phonemes. I know, for instance, that it can often take a second or two for me to differentiate Mandarin from Korean or Japanese when it being spoken quickly and loudly (such as when you first turn on a movie).

[retroflexzy]

(Disclaimer: I've not studied any of these languages in detail; the following is a mix of what I have studied, personal knowledge, and logical conclusions derived from both)

Structurally, Japanese and Korean is almost identical. The morphology system are similar, they have the same word order, are both tonal in a similar way, and there are even parallels that can be drawn in terms of their phonology; some words are even phonemically identical. However, their core inventory of phonemes is quite different: there are sounds in Korean that just do not occur in Japanese. Like Japanese, the categorization of Korean is debated; Wikipedia is helpful here if you want to know more.

Now, Mandarin Chinese is entirely different. The tonal system is different, it lacks an overt inflection system, word order is different, and the phoneme inventory is, again, different. While there is vocabulary sharing going on, it's hard to see any technical relationships between them.

I've heard a number of different stories on how the Korean peninsula and Japanese archipelago were settled by the Chinese, from the Chinese, but it just doesn't seem plausible considering the linguistics of the regions. What history I did study in Japan simply never mentioned it. And, to be honest, that is the extent of my historical knowledge of the languages.

[tel]

The story I hear (again from the Chinese) is that Korean is a dialect/divergence from Chinese that lost much of the tonality. I've not studied it personally, but from my knowledge it wouldn't be surprising for a Chinese speaker to believe Korean (and Japanese) lack tonal structure.

Japanese on the other hand is considered more likely to be separate but high influenced due to word sharing from the many wars between China and Japan. this seems pretty plausible considering the sharing of the written language which is widely considered to be Chinese in origin.

It's all interesting because I wouldn't be surprised if a lot of the ancient history is obscured by the three proud nations.