...a group of ten-year-old schoolboys.是什么意思？

...a group of ten-year-old schoolboys.

一群 10 岁的男学生

group

n. 组，团体，群，批，（雕塑等的）群像，（英美的）空军大队；vt.& vi. 使成群，集合；vt. 分类，归类；

例句
...a group of youths riding their motorbikes four abreast.
驾着摩托车，四个一排齐头并进的一群年轻人

of

prep. 关于，属于…的，由…制成；aux. 助动词 [非标准用语、方言] =have [主用于虚拟语气]；

例句
He did have a real knowledge of the country...
他对该国的确知之甚多。

schoolboys

n. （中小学的）男生( schoolboy的名词复数 )；

例句
Elizabethan schoolboys were taught adoxography, the art of eruditely praising worthless things.
伊丽莎白时代的男学生被教授“学述”学, 亦即博学地歌颂无益事物的人文学科.