时间一分一秒地过去了，我该上学了，可妈妈还未回家做饭，我心急如焚，正在这时，只听见楼梯上有人跑得气喘吁吁，开门一看，是妈妈。
A second time in the past, I have to go to school, but my mother had not come home cooking, I worried, at that time, only heard on the stairs, who ran pant for breath, open the door to look, mom.
youdao