what dates on the Jewish calendar is marriage prohibited?

Answer 1

prohibited is a strong word.

but their are several times when marriages are traditionally done and not done.

The 50 days between Passover and Succot is one major break.

The three weeks between the 17th of Tammuz and the 9th of Av is another.

Also fast days also dont have weddings.

The month of Adar (we are currently in it) and beginnings of the month are traditional times when many weddings do occur.