Here's something that's just caught my attention, and either it hasn't been covered in class, or it has simply evaded my attention:
If you want to say "Today is this and that day", for example, "Today is the 21st of December"...
...do you say:
Intuitively, I'd go with "今日は十二月二十一日です。" however, I have noticed that the drills routinely use the pattern "今日は十二月二十一日。" for all dates.
So, wich one is correct? The one with or the one without "です"?