英语翻译“He went into the forest,and he saw one standing there by six trees which he had rooted up as if they had been stalks of corn.”

整句话我给你从后往前分析吧,可能会更清楚些.
1.which he had rooted up as if they had been stalks of corn.
这是which引导的定语从句,前置词是trees.此定语从句本身又是一个复合句,后面带有一个 as if 引导的假设状语从句,并且此定语从句中的主句 he had rooted up 和 as if 从句都使用了虚拟语气.此定语从句的意思翻译出来就是：他把大树就像玉米杆似地连根拔起.
2.one standing there by six trees
one 是代词,这里指人.stand by 的字面意思是“站在...的旁边”,可以有引申意思“支持...”,这里在stand 后面加了一个there,就表明这个动词短语就是字面上的直接意思,而不是引申的意思.standing there by six trees 是现在分词短语做补语,进一步补充说明 one 的.此句群的意思翻译出来就是：（看见）一个人正站在六棵大树旁边.
注意,这里的树应该是大树,绝不会是小树或者树苗,因为从后面的虚拟语气的使用,可以看出说话人的意思是：拔大树就像是拔玉米杆似地容易.
3.He went into the forest,and he saw
这就是一个由 and 所连接的两个简单句,主语都是he,谓语分别是 went 和 saw.
最后,整个句子的意思也很明白了：
他走进森林,看见一个人正站在六棵被他像玉米杆似地连根拔起的大树旁边.