Question

—What will your parents do?
—They will go on a ______ visit to Beijing.   
A. seven day        B. seven-day        C. seven-days

Answer 1

B

试题分析： a seven-day visit一个七天的访问。有连字符时不能用复数形式。句意：你的父母将去做什么？他们将去北京参观七天。故选B。