。
She was taken in by his sweet talk.
Literal
She [topic-は] his [genitive-の] sweet words [by-に] was-deceived.
甘い言葉 ('sweet words, sweet talk') is a calque-ready idiom — both English and Japanese use 'sweet' (甘い) for flattering, persuasive language designed to seduce or manipulate. 騙される ('be deceived') is the passive of 騙す; the agent of deception (the sweet words) takes に. Implied tone is rueful — she fell for it.