Meanings of extensive periods in English

Due to unfortunate personal circumstances, I have been absent from the UK for extensive periods over the past four years.

For many mammalian genes, initiation of transcription during embryonic development must be subsequently sustained over extensive periods of adult life.

Hicks, 39, has detailed extensive periods of solitary confinement, severe beatings and forced druggings at the hands of his American captors.

They dominated play for extensive periods but could never shake off a gritty Meath side whose promotion prospects are now all but gone.

RNZI will still broadcast in analogue short-wave for extensive periods of each day, but there won't be a 24 hour service as there has been.