In romantic movies, how many of them starred by John Travolta?
romantic movies refers to Genre = 'Romance'; starred by John Travolta refers to Name = 'John Travolta'
SELECT COUNT(*) FROM movie AS T1 INNER JOIN characters AS T2 ON T1.MovieID = T2.MovieID INNER JOIN actor AS T3 ON T3.ActorID = T2.ActorID WHERE T1.Genre = 'Romance' AND T3.Name = 'John Travolta'