The U.S. and its P5 Plus 1 partners -- Britain, China, France, Russia, and Germany -- have a March 31st deadline for a framework deal with Iran. The deadline has already been extended twice. ____________________________________ 美国和5加1伙伴,巴西、中国、法国、俄罗斯和德国,将3月31日定为与伊朗达成框架协议的截至日期.截至日期已被推迟过2次.________________________________________________