But I could swear by your expression.

但是我可以从你的表情发誓。

youdao

I could swear I've been here before.

我敢发誓曾经来过这儿。

youdao

I could kill you! I swear I could!

我要杀了你！我发誓我要。

《柯林斯英汉双解大词典》

I could call many people to swear for this method.

我可以请许多人为这个方法担保。

youdao

But if I ever could, I swear I would love you for the rest of my life.

我配不上你，但如果我能的话，我发誓要爱你一生。

youdao

I swear, I could just strangle you!

我发誓，我可以掐死你！

youdao

I swear, I could just strangle you!

我发誓，我可以掐死你！

youdao