Many people swear by vitamin C's ability to ward off colds.许多人深信维生素C能预防感冒。I swear by God I didn't mean it.我对上帝发誓我不是这个意思.I thought I saw him leaving, but I couldn't swear by it.我好象看见他离开了, 但我不能肯定....

swear by的音标：swear by的英式发音音标为：[swɛə bai]swear by的美式发音音标为：[swɛr baɪ]...

以…的名义起誓，极其信赖...