新概念第二册语法问题 the food that had been laid out for the dead is thrown into

the food that had been laid out for the dead is thrown into a river or a sea 这里为什么用had been 而不是have been或者 was？？这样用意义是什么？？

had+done 是表示的过去时，这里的这个动作已经在过去就完成了，所以文中用的过去完成时
have+done 是表示的现在完成时
但是上文的 had been laid 其实是用的过去完成时的被动语态，是表示被怎么样。
如果是现在完成时的被动语态则是：have been done 。
希望能对你有所帮助。

这个问题问得很好，事实上我也有这个疑问！因为全文用的是现在时态，表示的是习惯： 新概念英语文本第二册Lesson 96 Lesson 96　　The dead return亡灵返乡　　 A Festival for the Dead is held once a year in Japan. This festival is a cheerful occasion， for on this day， the dead are said to return to their homes and they are welcomed by the living. As they are expected to be hungry after their long journey， food is laid out for them. Specially-made lanterns are hung outside each house to help the dead to find their way. All night long， people dance and sing. In the early morning， the food 【that had been laid out for the dead 】【is thrown into a river or into the sea】 as it is considered unlucky for anyone living to eat it. In towns that are near the sea， the tiny lanterns【 which had been hung in the streets the night before】， 【are placed into the water】 when the festival is over. Thousands of lanterns slowly drift out to sea guiding the dead on their return journey to the other world. This is a moving spectacle， for crowds of people stand on the shore watching the lanterns drifting away until they can be seen no more. New Concept English 是经典中的经典，英）亚历山大 （Alexander，L.G. ）是一个很严谨的编者。 但这两句话的时态，我怀疑有误。至少我还不能理解为什么用过去完成时而不用现在完成时。 原文的这两处，如果划空，让中国的学生填，98%会填现在完成时态，而不会填过去完成时态! 因为过去分成时态，如你所说，是相对于过去时间的过去。而这两句话的主句时态都是现在时态，而不是过去时态。过去完成时没有了可参考的“过去”时间。

that 引导的定语从句 that had been laid out for the dead 为死者准备的 定语从句修饰the food. 为死者准备的食物被扔进河里。