It would be much better for them to keep silent during this period of time.在此期间，他们最好保持沉默。The calculation is based on your average earnings during this period.这一计算是以你在这段时期内的平均收入为根据的。His whereabouts were quite unknown during this period.这一时期他几乎是下落不明。It was during this period that she took to drink. 她就是在那个时期开始酗酒的。