verb
BAD : He's going to ask her to marry with him.
GOOD : He's going to ask her to marry him.
BAD : His daughter is expected to marry to a viscount.
GOOD : His daughter is expected to marry a viscount.
BAD : After they get marry, they're going abroad.
GOOD : After they get married, they're going abroad.
◆◆◆
marry sb (WITHOUT with/to ): 'Isn't he the man who married Elizabeth Taylor?'
get married ( to sb ): 'I can still remember the day I got married. United were playing at Wembley.'