问题
选择题
Milk quickly turns sour _____ it's in a fridge. [ ]
A. until
B. since
C. as
D. unless
答案
答案：D
搜题请搜索小程序“爱下问搜题”
Milk quickly turns sour _____ it's in a fridge. [ ]
A. until
B. since
C. as
D. unless
答案：D