I know that he has tried hard; be that as it may, his work is just not good enough.

我知道他已经尽力了，尽管如此，他的工作仍不太理想。

《牛津词典》

It's just so hard to think about all of those practical things and make good work, you know.

你知道，要想把所有这些实际的东西都考虑进去并做好工作是很难的。

youdao

If anyone reads this and has just been diagnosed I know its hard but there is light at the end of the tunnel and just keep going on and never look back.

看到这里的时候你如果已经拿到了诊断结果，我知道这对你很艰难，但是你要相信漆黑通道的尽头还有一片亮光，继续前行吧，不必回头。

youdao

So I thought,'Okay then, stop thinking so hard and just do it,' 'cause I know I have it in me.

VOA: standard.2009.08.18

and just, you know, work hard and study, do your homework, eat well too, I'm sure that helps

所以，我的建议是，努力学习，认真完成作业，
同时也好好吃饭，这真的很重要哦。

如果是在考虑留学 - SpeakingMax英语口语达人

They just say, "It's just because!" It's hard to know exactly why it's "a".

他们只会说“没有为什么！”为什么用“a”很难确切搞清楚。

韩国人经常犯的失误 - SpeakingMax英语口语达人

And perhaps more than anyone else, I know just how hard this fight will be.

CNN: Clinton's September 17, 2007, speech on health care

And others say that Israel has to just, you know, hit hard these groups taking the soldiers and make sure it doesn't happen again.

NPR: Border Fighting Spurs Israeli Blockade of Lebanon

You know, it's hard to remember where we started just, you know, 15 months ago.

NPR: Obama Re-Writes History, Clinches Party Nomination