1、But today,more and more countries try to establish democratic systems,which enable people of diffe

题目

1、But today,more and more countries try to establish democratic systems,which enable people of different classes to involve in the management of the nation.
首先systems用复数对吗?因为前面有个countries,其次 enable sb to do sth在这用得对吗?还有其他地方是否有错误请帮忙一并改正
2、people’s welfare should doubtless be the best indication of a nation’s greatness.
doubtless应该用副词还是.应该放哪里比较好,请用语法角度解释下

答案