Are there difference between those sentences?
- Alex is getting married next month.
- Alex will get married next month.
Seems that the first one is expressed in present continues, and the second on in future tense. Am I correct?
The present continuous/progressive construct can be used to refer to a future event, typically a near-future event, especially if qualified with a time expression.
I'm going to the park tomorrow.
I'm leaving this job in two weeks.
She's testing the device next year.
There's little difference in meaning if a time expression is used. If a time expression is not used or able to be pulled from context, it could be confused with an actual continuous or progressive meaning.
John will get married. (We don't know when but we know he plans to get married. He's not in the process of doing that now, though.)
John is getting married. (He is either planning to get married or midway in the process of getting married. This is ambiguous unless context provides information.)