Are we having classes tomorrow?
Do we have classes tomorrow?
Are these questions above correct? Does one of them sound a more 'formal' way?
Are we having classes tomorrow?
Do we have classes tomorrow?
Are these questions above correct? Does one of them sound a more 'formal' way?
The first thing to recognize is that these two sentences are really asking about the current state of affairs of a decision as to whether there will be classes tomorrow. They aren't a request for a prediction about tomorrow's classes subject to all random circumstances. That is why they are present tense even though they refer to tomorrow's classes.
As @Davo mentions in comments on the question and here, there are some implied words that are missing. The meanings of the sentences are essentially "Are we (going to be) having classes tomorrow?" and "Do we have classes (scheduled for) tomorrow?"
Both of your sentences reflect common language. The use of present tense to refer to a future event in this case is understood to be shorthand for this meaning. If you were literally asking for a prediction about tomorrow's classes, it would be more correct to say "Will we have classes tomorrow?" (total absence of any present tense).
"Are we having" can be used in several ways. It can refer to ongoing current activity. It is also commonly used to refer to a decision about a future event, such as described in this question. "Are we having turkey for dinner" refers to the present decision rather than the actual future dinner.
""Do we have classes tomorrow" is understood to mean the same thing, but it is clearly missing some implied words. It wouldn't mean the same thing in reference to dinner. "Do we have turkey for dinner" would be asking whether we have turkey on-hand to prepare for dinner. So "are we having" and "do we have" wouldn't necessarily convey the same meaning in any sentence about a future event. In this example about classes, the meaning is the same.
As to whether one sounds more formal, "sounds" is the operative word. Both sentences are acceptable, and a form of common shorthand. "Do we have" is more direct, so "are we having" might have more of a formal ring to it.
Both are correct; the difference is mainly a matter of choice and taste. No one of them is really considered more formal than the other.
Are we having classes tomorrow.
is an interrogative form of present continuous tense. In present continuous we can use about past, present and future. (See here in the British council site). We can use it about the future for something which has been arranged or planned:
So practically speaking it is grammatically correct. Anyway, many people would use the phrase "going to", since we use We use going to to talk about plans decided before the moment of speaking (see here - British council)
"Are we going to have classes tomorrow?"
Regarding to the second choice:
Do we have classes tomorrow?
is an interrogative form of present simple tense, that can be used for future plans as well. (See here - British council)
So both choices are correct, and in conclusion: For future plans we can use present simple tense, present continues tense (with or without "going to"), and of course in future simple tense:
Will we have classes tomorrow?
For more details, read here: "Talking about the future" (An article by British council)
Both are correct."have" means "possess".On account of this("possess") meaning,simple tense use of "have" is preferred.Like, I have a cellphone,instead of,I am having a cellphone.
But when "have" imply different meaning than "possess", like when it is referring to an activity,event,plan,etc. then continuous tense other simple tense,can also be used.So,both of followings are right:
"We have a class today." "We are having a class today."
And,by extension, interrogatives are also correct.