问题
选择题
You have failed two tests. You'd better start working harder, _____ you won't pass the course. [ ]
A. and
B. so
C. but
D. or
答案
答案:D
You have failed two tests. You'd better start working harder, _____ you won't pass the course. [ ]
A. and
B. so
C. but
D. or
答案:D