C 试题分析:句意:再早五分钟,我们就赶上最后一趟地铁了。根据句意可知事实上没能赶上。Five minutes earlier,是隐含的虚拟条件句,相当于:If we had arrived five minutes,主句用could have done表示“过去本可能做却没有”,should have done “过去本应该做却没做”,选C。
选a 选b的话,可以这么说:we arrived at the station within five minutes before the last bus left. 就是去掉"to go ’‘意思是:我们在最后一班汽车出发的五分钟内到达。 within 是时间介词,有“范围内”的意思。 with后面常跟“工具性”的单词,表“伴随”,离最后班汽车出发还有五分钟~~ 差点弄错了,汗~~~