问题
选择题
The game is not very difficult _____ you understand the rules. [ ]
A. before
B. though
C. unless
D. once
答案
答案：D
搜题请搜索小程序“爱下问搜题”
The game is not very difficult _____ you understand the rules. [ ]
A. before
B. though
C. unless
D. once
答案：D