Ah, the vagueness of English. I remember years ago Babelfishing a letter that featured, "僕は退屈だ", Bokuwa taikutsu da. Here taikutsu means "boredom," and the automatic translation gave, "I am boring." And why wouldn't it? After all, this construction can be used in situations like, 今日は退屈だった, Kyou wa taikutsu datta,, "Today was boring," and you can put anything else in there to mean, X is boring. But the problem here is assuming that this pattern has the same meaning 100% of the time, and in this case it's not, "I'm boring," but "I'm bored" -- it can also be interpreted as, "As for me, it's boredom." Ah, the vagueness of Japanese!! The same thing can happen if you replace taikutsu da with another word, such as 怖い, kowai, "scary", which can be interpreted as "I'm scary," but means, "I'm scared." Since neither sentence can in any situation be interpreted as "I'm boring," " I'm scary," etc., context would lead one to the correct interpretation.
Japanese isn't alone into this dual interpretation of the same adjective -- we can take the Spanish word for "boring," aburrido, and with one form of "to be" it will have one meaning, and another meaning with ther other -- here soy aburrido uses the more "permanent" ser to indicate a more permanent condition -- I'm BORING, rather than the probably intended estoy aburrido, "I'm bored" (using the "temporary" estar).
I'd love to see other examples of the same adjective having very different meanings, dependent only upon one change elsewhere (or better sitll, NO change!).
AND BECAUSE THIS ARTICLE IS SO SHORT: If you read Mandarin Chinese (and even if you don't), you can
take a look here at this article on obscure and extremely complex Chinese characters. Biang (as in the noodle with the 50+ stroke character) is of course there, but you should see the monstrosity substitute character for "river"!