The most obvious way is to keep them indoors at times of sexual activity.
The 1940s and '50s were a time of intense literary activity.
Even at times of little activity, life in the trenches could be grim.
Their main time of activity is around dusk and dawn.
The thirteenth century was a time of activity and development.
Its time of activity always began after the office building was deserted and darkened for the night.
It was a time of considerable activity and excitement in the design studio.
This was a time of intense political and social activity in India.
With each note you should record the time, distance, and mode of activity.
Those first few months in office were a time of intense activity.