This painting was sold to a museum in New York in 1997.

这是我自己整理的,（每个公式中的done表示过去分词）
过去德被动语态有四种情况,如下：
1.一般过去时.
was/were+done
e.g:He is seen to go out of school.
2.过去进行时.
was/were+doing+done
e.g:The room was being cleaned this time yesterday.
3.过去将来时.
would be+done
e.g:He told us that the new railway would be built the next year.
4.过去完成时.
had been+done
Our classroom had been cleaned last Tuseday.
【其实被动语态不会特别难,只要去套我上面给你德公式就可以了,】
fighting!