I know I should stop smoking—don't give me a lecture about it.

我知道我该戒烟，别再教训我了。

《牛津词典》

I know I should be humble, but I'm so handsome that everybody stares at me.

我知道我应该谦逊一点，但我真是太英俊了，每个人都盯着我。

youdao

I know I should take exercise, but I never do.

我知道我应该进行体育锻炼，但我从来没这样做过。

youdao

COSTELLO: "You gonna be the coach,too?" ABBOTT: "Yes." COSTELLO: "And you don't know the fellows' names?" ABBOTT: " Well,I should." COSTELLO: "Well,then, who's on first?"

VOA: special.2009.03.09

I know I should be humble, but I'm so handsome that everybody stares.

我知道我应该谦逊一点，但我真是太英俊了，每个人都盯着我看。

so that 实战 - SpeakingMax英语口语达人

Right. I would say as I reflect back on my college experiences and those listening in the audience should know, I graduated from college 45 years ago.

的确如此，可以这么说,当我回想我的大学生活的时候,想必听众中有人知道，我45年前就从大学毕业了。

普林斯顿公开课 - 人性课程节选

But much of it is common sense, in an "I know I should do that, but I never actually do" kind of way.

FORBES: Time Management Secrets Anyone Can Use

"I know I should get at least 30 minutes of physical activity in every day, " says Christopher Edginton, a 66-year-old professor of leisure services at the University of Northern Iowa who took niacin for several years.

WSJ: New Rules for Boosting Good Cholesterol

Ms. ATTWOOD: Yeah, in fact, recent developments - I don't know if I should talk about them - but Jackie Selebi, there was a warrant out for his arrest.

NPR: South Africa Considers Legalizing Prostitution