1Congress has obstructed efforts to create a more straightforward visa for agricultural workers that would let foreign workers stay longer in the U.S. and change jobs within the industry.
主干主语：Congress；谓语：has obstructed；宾语：efforts
结构主句后接不定式短语 to create... 作 efforts 的后置定语；agricultural workers 后跟关系代词 that 引导的定语从句，修饰 visa；从句谓语 would let 后接复合宾语 foreign workers stay... and change...，and 连接两个并列的不带 to 的不定式。
译文国会一直阻挠设立一种更简便的农业工人签证，这种签证本可让外籍工人在美国停留更久，并在行业内换工作。
考点that 引导定语从句修饰 visa，而非 workers · let sb. do 结构中不定式不带 to
2Today’s farm laborers, while still predominantly born in Mexico, are more likely to be settled rather than migrating and more likely to be married than single.
主干主语：Today’s farm laborers；谓语：are；表语：more likely to be settled... and more likely to be married...
结构主语后插入 while 引导的让步状语从句（省略 they are）；主句用两个并列的 more likely to be... 结构，rather than 连接 settled 与 migrating，than 连接 married 与 single，形成对比。
译文如今的农场劳工虽然仍以墨西哥出生者为主，但更可能已定居而非流动，也更可能已婚而非单身。
考点while 引导让步状语，可省略主语和 be · rather than 与 than 分别构成对比
3Production of corn, cotton, rice, soybeans, and wheat has been largely mechanized, but many high-value, labor-intensive crops, such as strawberries, need labor.
主干主语：Production；谓语：has been mechanized；转折后主语：crops；谓语：need；宾语：labor
结构but 连接两个并列分句；前一分句用现在完成时被动语态；后一分句主语 crops 带前置复合形容词 high-value, labor-intensive，后接 such as strawberries 作举例插入语。
译文玉米、棉花、水稻、大豆和小麦的生产已基本实现机械化，但许多高价值、劳动密集型作物（如草莓）仍需要人力。
考点such as 引导插入性举例，不影响主谓一致 · 复合形容词 labor-intensive 作前置定语
4The H-2A visa has no numerical cap, unlike the H-2B visa for nonagricultural work, which is limited to 66,000 a year.
主干主语：The H-2A visa；谓语：has；宾语：no numerical cap
结构unlike 介词短语作状语，引出对比对象 the H-2B visa；其后 which 引导非限制性定语从句，修饰 H-2B visa，补充说明其年度限额。
译文H-2A 签证没有数量上限，这与每年限额 6.6 万份、用于非农业工作的 H-2B 签证不同。
考点unlike 引出对比，后接名词短语 · which 非限制性定语从句补充说明限额
5The shortage is compounded by federal immigration raids, which remove some workers and drive others underground.
主干主语：The shortage；谓语：is compounded；状语：by federal immigration raids
结构被动语态主句后接 which 引导的非限制性定语从句，修饰 raids；从句中 and 连接两个并列谓语 remove... and drive...，others 后省略 workers。
译文劳动力短缺因联邦移民突击检查而加剧，这些行动赶走部分工人，并迫使其他人转入地下。
考点which 非限制性定语从句修饰 raids · drive sb. underground 为固定搭配