上万的英文：
over ten thousand

参考例句：

Over the years, thousands of citizens fled to neighbouring countries
几年来，成千上上万的居民逃往邻国。

The world is always more interested in the one nun who goes over the wall than the thousands who don't
世人对一个还俗的修女，总比对成千上万个不还俗的修女更感兴趣。

over是什么意思：
adv. （倒）下；从一边到另一边；越过；再；结束
prep. 在…之上；越过；在…的另一边（对面）；由于；从一边到另一边
adj. 过去的；结束的；外面的；上面的
v. 越过

chew over; think over
考虑;详细讨论

I have failed over and over and over again in my life.
我一生中失败了一次又一次。

"Over shoes, over Boots"
一不做,二不休

ten是什么意思：
num. 十，十个

Tens of thousands
成千上万

Ten times ten equals one hundred.
十乘以十等于一百。

The clock struck ten.
时钟敲响十点。

thousand是什么意思：
n. 一千；一千个；无数
adj. 无数的

Tens of thousands
成千上万

The town has a population of ten thousand.
这个镇有一万人口。

A thousand people attended the conference.
一千人参加了会议。