Question

【题目】Bill is ten years old．He has a _________ sister.
A.4 years old
B.4-year-old
C.4-years-old
D.4 years'old

Answer 1

【答案】B
【解析】句意：比尔十岁了。他有一个四岁的妹妹。A． 四岁；B． 四岁的；C和D属错误表达。固定结构表示几岁的：基数词-year-old． 故选B。