in the children." The scientists reported that the risk of the disorder was almost double in children with high levels compared to those with no measurable level.

VOA: special.2010.05.26

At this point, we have no other choice but to double up before going to the next energy level, 2px so we'll put a second one in the 2 p x.

在这点上我们没有其他选择,而只有双倍填充,在到下一个能级之前，所以我们放入第二个电子至。

麻省理工公开课 - 化学原理课程节选

The current level is already nearly double what the United States had in Afghanistan last year, and some officials, including Secretary Gates, have expressed reluctance to send more.

VOA: standard.2009.08.11