Have you finished you work ? Yes, I have finished it . I finished it 1 hour ago.
A. already ,yet ,/
B. yet , already, /
C. yet ,yet, since
D. yet ,already, since
网友回答
A. already ,yet ,/
(答案→)B. yet , already, /
C. yet ,yet, since
D. yet ,already, since
解析：already多用于肯定句，表示一事实 意为 已经 早已;yet则多用于否定句、疑问句，意为 还、尚、迄今、到那时。Since表示自从……以来。句意:你已经完成你的作业了吗?——是的，我已经完成了。我是一个小时前完成的。1 hour后已有副词ago，故不再用介词since，故选B。