Tens of thousands of demonstrators had rallied outside the b

Tens of thousands of demonstrators had rallied outside the building on the
night of 4 December and the following day in protest at what they described as
Mr Morsi's illegal decrees giving him sweeping powers and also his drive to
change the country's constitution.
at what they described as Mr Morsi's illegal decrees giving him sweeping powers and also his drive to change the country's constitution.what在此怎么翻译啊.后半句的句子结构为