In an effort to reduce their inventories, Italian vintners have cut prices; their wines are priced to sell, and they do.

网友对这个句子中的 and they do的理解是错误的。错误的原因有三：

1 这个do显然是操作词替代。are priced中有操作词are, 不可能再使用助动词do, 所以do只能替代 do sell.

2 前面的their wines are priced to sell. 不定式to sell为目的状语，其逻辑主语为wines。sell为不及物动词，something sells= something is bought by people.

3 and they do = and they do sell. 其中they指的是their wines，而不是Italian intmers。and they do 意为：这些酒确实有人买，人们确实买他们的酒。

现在看句子意思，and they do是否是多余的：

为了减少库存，意大利酒商降低了价格。他们标出了低价以便人们购买，而这些酒确实销售不错。