Grammar help?

Both sentences are grammatically correct. The second appears stilted unless the speaker wants to aver that Marks joining doesn’t happen any other day besides today.

No.

Neither of them make sense. However if you are just evaluating the need for present tense the first one would be the opted answer. Otherwise neither because once you join it has become a past tense. So you might say Mark will join the contest today (future tense). By adding the word today, you’ve implied it has been done already during the day. Mark joined the contest today.

It is one of those funny verbs that because of its meaning cannot be completely used in context by its conjugation.

Mark joins the contest. (no time reference: present tense indicates that it may happen more than once)

Mark does join the contest today. (should not use a time reference with does… and does is an aux-v that should primarily be used only in questions or as “doesn’t” for negatives)

The time reference is unclear… either it already happened EARLIER today…

Mark joinED the contest today.

Mark has joined the contest today. (very recently)

… or will happen LATER today…

Mark WILL join the contest today.

Hope that helps.

Neither one sounds correct but I think the first one is better. I don’t think you need the word does. I would rather say. Mark is going to join the contest today or Mark will be joining the contest today.

i think both are correct. just the second one ‘stressing’ that Mark really is there in the contest.

Well i guess they both make sense but i think the first one is more grammatically correct.

i think both is correct but the

first sentence is the best. its sound good!