Any of our new products shall go through a 1 - 3 month testing period.

我们的任何一件新产品都有一至三个月的试用期。

Daniel McGrath of NCES said these are some of the largest decreases they have observed in a single testing period in 50 years.

全国教育统计中心的丹尼尔·麦格拉思说，这是他们在50年来观察到的单次测试中最大的降幅之一。