一道填空题Last week,he________on it for a long time until it looked like new.(work)
问题描述：
一道填空题Last week,he________on it for a long time until it looked like new.(work)
Last week,he________on it for a long time until it looked like new.(work)
答
Last week,he has been working on it for a long time until it looked like new.(work)
因为是过去一段时间一直在做一件事,所以用完成进行时最恰当,表示过去一个时间段一直在做一件事情且和现在有关系,就是上周他一直在做这个做了很长时间,直到它看起来像新的一样