I never leave the house without my book, and if I'm taking a train I'll usually have a back-up book in case I finish the first one.

我从来不会不带书出门，如果是搭火车的话，我一般会准备一本备份的，以防第一本读完。

youdao

I swear (that) I'll never leave you.

我保证决不离开你。

《牛津词典》

Now I shall never, never leave you again!

现在，我绝不，绝不再离开你！

youdao

It is true that I can never leave this garden.

VOA: special.2009.05.30

If I want to persuade you that I love you, would never leave you, you can trust me with everything, it may be a superb tactic for me to believe it.

如果我想让你相信我爱你，永远都不离开你，你什么都可以信任我，或许最好的策略便是我自己对此深信不疑。

耶鲁公开课 - 心理学导论课程节选

As long as I can recreate these images, I never quite leave home.

NPR: Natural Links in a Long Chain of Being

And I will never leave your side fighting for justice, for America's workers.

CNN: Gephardt: 'Never give up, never give in'

"The soldier's creed says 'I will never leave a fallen comrade, '" Pogany says.

NPR: Former Soldier Helps Others Fight Army for Help