significant period of time meaning in English

在较长时间内

Liquid must not be allowed to dwell for significant periods of time in any part of the equipment .
决不允许液体在生产设备中任何部位停留很长时间。
The new requirements also recognise the changes in the migration programme over the years which have resulted in an increasing number of people spending significant periods of time in australia as temporary residents prior to becoming permanent residents
此新法也承认这几年来，移民方案的变迁，以至于有越来越多的人在成为永久居民前，花了许多时间以暂时居民的身分停留在澳洲。