The experimental results showed that the microbe acclimation period for hydrogen sulfide and toluene were 16 and 32 days respectively by using modified bio-peat packing. 研究结果表明,采用改性泥炭生物填料净化含有硫化氢和甲苯的恶臭废气,降解硫化氢的微生物驯化期为16 d,降解甲苯的微生物驯化期为32 d。
After an acclimation period of a week, rats were randomly assigned into 6 groups, which were respectively described as control group, 0.75, 1.5, 2.5mg/kg mercury group, DMPS prevention group and DPA prevention group. 实验时，按大鼠体重随机分成6组，每组8只。 分别为：对照组、0.
That period was a bright page in the history of Chinese literature. 那个时期是中国文学史上光辉的一页。
Let us hope that the period of this injustice will be over soon. 让我们希望这个不公正的时期很快结束吧。
Childhood is a period of rapid growth. 幼年是生长迅速的时期。