But the first people who were like ourselves lived so long ago that even their sagas, if they had any, are forgotten.

the first people who were like ourselves ^{远古人类 = fossil man（替换）}

• Scientists discovered a skull of a fossil man. ^{科学家发现了一块化石人类的头骨}
• We know little about the people who lived long ago. ^{我们对远古人类了解甚少}
• The first 'modern men' appeared in Africa. ^{最早的现代人出现在非洲}
• Some tools used by ancient men were found in the cave. ^{在洞穴中发现了一些古代人类使用的工具}

first people who were like ourselves ^定语从句 = first people like ourselves ^后置定语

• ... asked to see a dress that was in the window. = ... asked to see a dress in the window.

Your school may have done away with winners and losers, but life has not. In some schools they have abolished failing grades; they'll give you as many times as you want to get the right answer. This doesn't bear the slightest resemblance to anything in real life.

if + 从句^{（让步用法） 即使}

• God’s reasons, if He has any, are opaque to us. ^{上帝的理由，即使他有，也是难以理解的}
• There is every likelihood that the costs will outweigh revenue, if there is any. ^{成本极可能超过收入，即使收入存在}
• His descendants, if any, never left the island. ^{他的后代，即使有，也从未离开这座岛屿}
• He is seldom, if ever, absent from work.

There is every likelihood that the costs of the monitoring system, such as the purchase, maintenance and updates of software, employment of extra personnel in charge of it, will offset or even outweigh additional revenue, if there is any.

So archaeologists have neither history nor legends to help them to find out where the first "modern men" came from.

neither...nor... ^{既不…也不…}

• Neither the teacher nor the students were in the classroom. ^{老师和学生都不在教室}
• Neither the evidence nor the witnesses support his claim. ^{既没有证据也没有证人支持他的说法}
• Neither John nor Mary likes sushi. ^{约翰和玛丽都不喜欢寿司}

find out ^{查明；弄清楚}

• Scientists are working hard to find out the cause of the disease. ^{科学家正努力查明这种疾病的原因}
• She called the company to find out more information. ^{她打电话给公司了解更多信息}
• We need to find out what happened last night. ^{我们需要弄清楚昨晚发生了什么}