I oftenly think about this. We were just college students. We didn’t have a plan. We had no resources. How did we build the biggest community in the world with more than 1.5 billion people? We just cared more.
我经常想关于这个。那时候，我们只是学生。我们没有一个计划。我们没有副 资金（resources). 我们怎么创造15亿（1.5 billion /billion=10亿(1000000000) so 1.5billion=1500000000=15亿）人的社区（network）?最大的社会有差不多了1.5 billion 人民？我们比它他（"它"used to describe animals and inaniate objects.”他“refers to people,but if it a women,used”她“）们就关心多的的多。

At every step of the journey, people doubt new ideas will work. We faced many problems and had to change many times. We started off as a small service for students in America.
当路中过程中的每一步，人民人们怀疑他们的思想可能不好这个想法是否能实现。我们有了很多问题也应该不得不改变很多次。我们开始的时候是一个为美国学生的小产品提供服务。

The interesting thing is that I did not even think I might build this product. I was just a college student. I thought a big company like Microsoft or Google would build this. They had thousands of engineers and hundreds of millions of users. They should have built the social network for the world. Why didn’t they?  

thousands of 数以千计 

 hundreds of millions of 数以百万计
是有意思的是我从来不想没想过我可能创造这个产品。我只是一个学生。我想像微软(Microsoft)或 谷歌(Google)这样最大的公司会做这个。它们有了很多（You can use a more  advance word成千上百.An Chinese four-character idiom ）的工程师和用户。它们本应做了世界的网络社交网络（social network for the world）。为什么它们没做？

我同学/My Classmate