og 129为什么do不能指代are priced to sell?

看了链接里得所有讨论。大多集中在they的指代问题上，但是为什么没人置疑do是什么东东的省略呢？do既然做they do句子中的谓语动词那么它应该指代前半句话中的谓语动词才对啊，也就是their wines are priced to sell 中的are priced.,怎么会指代不定式to sell呢？

这怎么会叫平行呢？

their wines are priced to sell, and they do

题目贴一下先：

In an effort to reduce their inventories, Italian vintners have cut prices; their wines have been priced to sell.
and they are.
(A) have been priced to sell, and they are
(B) are priced to sell, and they have
(C) are priced to sell, and they do
(D) are being priced to sell, and have
(E) had been priced to sell, and they have

这是一种表示强调的用法，例如 Do you like it? Yes, I do. 要求前后时态一致。are priced是被动，sell是主动，但都是现在时。

菜鸟手册上是这么解释的      

注：1、从解释中可以infer出来，they 必须指代 wines（由此判断后边省略的只能不定式to sell）；their可以跨过分号指代前边的vintners.

2、sell 可以做不及物动词，被卖出去。

3、大并列的感觉 (本题会不会作并不重要，重要的是要知道ets是多么的重视并列，而并列应首先考虑本质上并列：本题中do sell 中sell是不带to的不定式)。

4、本题所有的错误选项在时态上都存在不一致的感觉。

建议MM做题时不要太拘泥于语法，看懂句意，也有很大的帮助。毕竟GM不是T。