The community feature, size-class structure, the regulation of changing density were analyzed and the survival curve, the death curve and the life table were worked out.

分析了白皮松的群落学特征、径级结构及其密度变化规律；绘制了存活曲线和死亡曲线，从多角度研究了白皮松幼林种群的动态变化规律。

youdao

Does the quality of teaching depend on class size?

教学质量取决于每个班的人数吗？

《牛津词典》

He suggested a link between class size and test results of seven-year-olds.

他建议把7岁儿童的班级大小和考试结果相关联。

《柯林斯英汉双解大词典》

By keeping women under the household of the men of their original family, the upper-class Romans tried to balance these different households in size and importance.

所以女子保留娘家的家户关系，有助于罗马上层阶级,平衡不同家户的规模及地位。

耶鲁公开课 - 新约课程节选

Medium-size M-class flares can cause brief radio blackouts in the polar regions and occasional minor radiation storms.

MSN: Big sunspot unleashes an intense solar flare

Even in the hardest-hit economies such as Spain, Ireland, or Portugal, groups of healthy small- and medium-size businesses and middle-class households exist that constitute good risks.

FORBES: How Europe's Banks Can Return To Health

The state pre-schools, however, fall short of set standards for class size and staff-to-pupil ratios.

ECONOMIST: Despite budget cuts, reformers are pushing ahead