half of 后跟可数名词的单数复数均可。
An half of a pencil is here.
这有半截铅笔。（可以接可数名词单数）
Half of them are gone.
她们之中的一半人走了。（可以接可数名词复数）。
Half (of) the students in that school are from the countryside.
那个学校有一半学生来自农村。(of+名词时，of可以省略)。
Only half of them came last Sunday.
上星期天他们中只有一半人来了。
half of后面加单数也可以接复数，中文意思是“……中的一半”
阿森纳队在上半场比赛中占据上风。Arsenal dominated the first half of the match.
行政事务占用了我一半的时间。Administrative work occupies half of my time.
上半场比赛打得十分沉闷。The first half of the game was pretty dull.
