Translation:Tomorrow will be December twentieth.
Hell in some regions people say "twentieth December" (with an implicit "day of" in between). I almost feel more tested on my English than on Japanese here!
No. It's just the answers are for American English. The answer should be correct
Maybe it's a regional thing but I could see it being used either way where I live (in America).
That's just the way it is. The number twenty seems to be important for the Japanese. For example: "twenty years old" in Japanese is: 二十歳（はたち）. All other ages end in -さい: 一歳（いっさい）、二歳（にさい）、三歳（さんさい） etc.
Is it correct to say that in English using the present tense? "Tomorrow is December the 20th"?