Is it ok to answer only the day of the month to the question "今天几号?"?
-- 今天是八月二十号. (it is OK, common phrase)
-- 今天是二十号. (is it Ok? Why not?)
If the second dialog is not grammaticaly correct, how can I ask for a day of the month?
It is ok to use month when asking 你的生日是几月几号? But the date (month + day) is asked without month (from book 汉语会话301句) just 今天几号?