dwell in (someone's) thoughts

Translations
жить в мыслях (кого-то)
The memory of their last vacation continued to dwell in her thoughts.
Воспоминание об их последнем отпуске продолжало жить в её мыслях.
Definitions
To occupy or remain in someone's mind for a significant amount of time, often because of strong emotions, memories, or preoccupations related to that person or subject.
Words
dwell

verb
пребывать
in

preposition
в
someone's

pronoun
чьих-то
thoughts

noun
мыслях