应该去北京英语可以说成 "I should go to Beijing."

这句话的来源可能来自于你想要去北京旅行或工作，或者因为你有其他原因需要前往北京。

例句：

I've always wanted to visit Beijing. I think I should go there someday.
My job requires me to travel to different cities, and next month I have to go to Beijing.
I have some family in Beijing, so I should go visit them sometime.

中文翻译：

我一直想去北京旅游。我想有一天我应该去那里。
我的工作需要我去不同的城市旅行，下个月我必须去北京。
我有一些家人在北京，所以我应该去看望他们。