－A

问题详情：

－A _______ schoolboy, Li Da decided _______ across the river.

     －Good boy!

A. 12-years-old, to swim   B. 12-year-old, to swim 

C. 12 years old, swimming  D. 12 year old, swimming

【回答】

B

知识点：构词法

题型：选择题