The country has already sent up three unmanned spacecraft ,the most recent (having been launched) at the end of last Mar
The country has already sent up three unmanned spacecraft ,the most recent (having been launched) at the end of last March.
括号内have为什么要加ing
这是 现在分词完成形式的 独立主格 结构 所以 have要加ing. ���еĶ�������Ͳ���ing������ing����have been launched ����ν����ʽ���ɵ��Dz��о� ��Ӧ����һ���ȥʱǰ��Ӧ��and ��, and the most recent was launched at the end of last March.��֮ ����ing �Ͳ��� ���ڷִ� �Ķ�������ṹ��˼��˵�������������ӣ�����ing��û�������������ֲ�ͬ �ı�﷽�� ԭ�� �� �������� �ṹ ��״�� ��Ȼ˵�� �������Զ���Ҳ���������� �� the most recent ��Ϊ �����Ѿ������ �� �� ���ڷִ� �������ʽ ��������� �� �����Բ������ʡ�ע�� ���� ��˼һ�� ע��ֱ�1��������ṹ2 �������Զ���Ӿ�3 ���о�1The country has already sent up three unmanned spacecraft , the most recent (of them )having been launched at the end of last March.2The country has already sent up three unmanned spacecraft , of whichthe most recentwas launched at the end of last March.3The country has already sent up three unmanned spacecraft , and the most recent (of them )waslaunchedat the end of last March. the most recent= the most recent one����ʱ������������һ�� ���ϸ����µ� �Ѿ����䡣��ʱ��״�����Ҿ��Dz��ܹ����the most recent�����������Զ���Ӿ䲻Ҫ�����of which���� �����Զ���Ӿ�� ����� ��ʼӹ�ϵ����������û�����Ҳû�����ʣ�����the mostrecent ������������ԭ������û�����Ҳû�����ʣ�����the mostrecent �������ڷִʵ����������ɶ�������ṹ���Dz��Ǿ�����ν��ϵ������have��Ҫ��ing��� �� ���ڷִ� �� ��������ṹ ��Ȼ Ҫ�����ڷִ� �� his mother being ill ��he had to stay at home to look after her.=because his mother was ill ,he had to stay at home to look after her��Ϊ ���ڷִ� �������� �� �������� ��һ������ �����ڷִ�ǰ�� �����Լ��� ������ �������ڷִʵ� ��������ṹ ����� һ�� ���������ڷִ� ��״���� being ill ��he had to stay at home ��=because he was ill ,he had to stay at home.