Promise you won't tell.

你要保证不往外讲。

《牛津词典》

If I were to promise you a holiday on the thirtieth of the month after next, do you think you would forget the date?

如果我答应你下个月30日休假，你认为你会忘记这个日期吗？

youdao

Don't listen to those who promise you wealth overnight, my boy.

孩子，别听那些许诺一夜暴富的人的话。

youdao

if you chose Chicago, I will promise you this: Chicago will make America proud and America will make the world proud,"

VOA: standard.2009.09.16

And your roommate says, "Inside the envelope are facts about this milkshake that if--I promise you it is indeed the case-- if you knew these facts, " you would not drink the milkshake anymore."

而你的室友说，“在信封里面是关于奶昔的事实,如果，我保证里面是事实-,你知道了这些事实，你就不会再喝奶昔了“

耶鲁公开课 - 死亡课程节选

So it is my promise to you and it is the huge staff's promise to you that we will absolutely get you through this course and you will have a good time doing so.

所以我对你们承诺，也是所有教员的承诺：,你们绝对能够通过这门课程,并且在课程中度过一个愉快的时光。

哈佛公开课 - 计算机科学课程节选

Listen to me, I promise you that no harm will come to the children.

NEWYORKER: The Slows

And I promise you we'll use every legitimate means to free your loved ones from captivity.

CNN: Iran-Contra Affair

So I promise you our problems can be solved, and our challenges can be met.

WHITEHOUSE: The White House