This is the 5553rd most frequent Turkish word.
mısınız
"Are you?"
In this sentence, 'mısınız' functions as a second-person plural/formal singular interrogative suffix, asking someone if they are intending to attend the event indicated by the verb 'katılacak' (will participate).
Koşuya katılacak mısınız?
Are you going to participate in the run?
Here, 'mısınız' is used to inquire about the action of meeting up at the café, aiming for confirmation or denial of the described action.
Kafede buluştuk mısınız?
Did you meet up at the café?
In this usage, 'mısınız' is employed to question commitment or resolve toward a subject, providing a polite form of inquiry.