问题补充:
Peter is a boy. His younger brother is .
A. ten-years-old ; six years old
B. ten years old ; six years old
C. ten years old: .six-years-old
D. ten-year-old ; six years old
答案:
A. ten-years-old ; six years old
B. ten years old ; six years old
C. ten years old: .six-years-old
(答案→)D. ten-year-old ; six years old
解析:第一空ten-year-old是复合形容词,表示“十岁的”,三个词之间有连字符,名词用单数。第二空做表语,不用连字符,名词用复数。