To attach the preparatory to the senior school these three classes were known officially, on speech days and in reports, as upper, middle, and lowersecond.
作为高中的预备班，在演讲日和报告中，这三个班被正式称为上、中、下二班。
2
Further study showed that the reason for the obvious enhancement of phosphorus removal efficiency was mainly the SBR2 system lowersecond phosphorus release amount.
进一步研究表明，除磷效率得到显著提高的原因主要是SBR2系统较低的二次磷释放量。
3
Second, yield growth has been lower in wheat and rice than in corn and soyabeans.