In English, "today" can be a noun or an adverb, but many European languages see it only as an adverb. So, the "today" in "Today is Wednesday." is seen as an adverb.
Can anyone explain time nouns and adverbs of time to me?
Can 最近 be a noun and an adverb?
What part of speech is 上个月？Can it be an adverb?
Can 昨天 be a noun and an adverb?