昨日 yesterday 先週 last week 去年 last year Why does this language keep looking for a different way to say "last"?
You don't say "last day" in english either ;) From the kanji meanings i got something like: previous-day, past-week, gone-year. I guess you could say that because these different concepts have different degrees of "pastness" (last year is generally further away than yesterday) Japanese uses different words to describe them. But I don't speak Japanese too well, just thinking of an explanation.
It is because those characters were taken from different registers of Chinese at different times.
Why is the translation given in katakana but the answers given all in hiragana? It makes it really hard to learn new words, and what's the use of giving translations if I have to look it up elsewhere anyway?