If you swear by something, you believe that it can be relied on to have a particular effect. ( INFORMAL )
Many people swear by vitamin C’s ability to ward off colds.
PHRASAL VERB : V P n
If you swear by something, you believe that it can be relied on to have a particular effect. ( INFORMAL )
Many people swear by vitamin C’s ability to ward off colds.
PHRASAL VERB : V P n
Collins COBUILD Advanced Learner's English Dictionary. Английский словарь Коллинз COBUILD для изучающих язык на продвинутом уровне. 2006