Translation:What is today's date?
Yes, you are right! We learn Chinese but not Chinese English. This is a big problem when traveling in Asian countries: people think that they speak English. In reality, they speak in their native language using English words and sometimes their sentences do not make any sence...
Dunno what to say exactly, but I learned it without 是, and have always said it without 是. Mandarin often has sentences without 是, where standard English would normally use "is". If you want a more word-for-word translation, I'd say "Today how many months how many days?" You can also simply ask 今天几号？