你知道那仅仅是近似值。用英语怎么说？

你知道那仅仅是近似值。

That's just an approximation, you understand.

just

adv. 刚才，仅仅，只是，正好，刚要；adj. 公正的，合理的，恰当的，合法的，正确的；

例句
It became very clear that the incident was not just an aberration, it was not just a single incident.
事实已经很清楚，这件事不是偶发的，它并不是一起孤立的事件。

an

art. 一（在元音字母前代替不定代词a），一任一某一，一个；

例句
He started eating an apple...
他开始吃苹果。

approximation

n. 接近，<数>近似值，近似额，粗略估计；

例句
That is a fair approximation of the way in which the next boss is being chosen.
那和下一任老板的选任方式相当类似。

you

pron. 你，你们，您们，各位，大家；

例句
I suggest you leave it to an expert...
我建议你把它留给专家来解决。

understand

vt.& vi. 懂，理解；vt. 了解，默认，听说，领会；

例句
Another accusation levelled at the Minister is that he does not understand ordinary people...
另一个矛头则直指部长不懂得体恤百姓。