So far, I do not know of any study that I could call upon in order to prove what I just said, but my own experience tells me this is the case.

迄今为止，就我所知，并没有相关的研究(这是我强烈呼吁的)可以证明我的看法，但我的经验告诉我存在这样的情形。

youdao

It is both satisfying to know that I have recovered so far, and frustrating not to have recovered more.

这既让我对我已经恢复了很久感到满意，同时却懊恼恢复的太少。

youdao

If you do not come, and if I do not hear from you, then I shall know that you could never be happy so far from the people and the country which you love.

如果你不来，如果我听不到你的回信，我就会知道，如果你离开你挚爱的亲人和乡土，你是不会幸福的。

youdao

What I just spent many lectures discussing is the fact that we can not know how far away an electron is from the nucleus, so we can't actually know the radius of a certain atom.

我花了这么多课时所讨论的正是我们,不可能知道电子离原子核有多远这一事实，因此我们不可能知道某个原子的半径。

麻省理工公开课 - 化学原理课程节选

Mr. BLAIR: You know, the way the whole situation unfolded, I was never given an opportunity, even though at one point during the incident, I tried to, you know, give them an opportunity to identify who I was and that, you know, I lived not too far from where I was stopped from.

NPR: Gates' Arrest All Too Familiar For Black Reporter

As far as I know, President Obama does NOT go round telling voters that high unemployment is a "small price to pay" for a historic rise in productivity.

BBC: The UK productivity puzzle (cont'd)

"Those who know me know that my interests are wide-ranging and far-reaching, and I will not let it define what I do in this chamber - certainly not, " he declared.

BBC: Queen's Speech debate: Education and health