Of course, it is not possible to know for sure why France had a revolution and England did not.  We must also note that France’s revolution happened before Marx was born and therefore was not something that he predicted.

That said, we can make some conjectures about why France had a revolution and England did not.  The main reason for this is that France had a much less liberal and democratic system than England did.  By the time of the French Revolution, England had a system in which Parliament had a great deal of power and the monarchy was limited.  The system was not democratic in our view, it was quite democratic for those days.  The French system, by contrast, gave very little power to the people. 

This is the main reason why England did not have a revolution.  It had a system that was much more democratic.  That let off some of the pressure from the people.  The people had some way of having their ideas heard and therefore they were less frustrated and less likely to rebel.