7、直延续到现在,还会一直延续下去。(含有一定的感情色彩)消防员们已经工作24个小时了。Thefiremenhavebeenworkingfor24hours.(辛苦了)我已经等了两个小时。(等得好辛苦)I have been waiting for two hours.自上周星期日以来就一直在下雨。It has been raining since last Sunday.It has been raining since last Sunday.自上周星期日以来就一直在下雨。forcenturies几个世纪for+hours/days/weeks/mon