If a computer crashes, you will lose the file you ________ on unless you save it regularly.
If a computer crashes, you will lose the file you ________ on unless you save it regularly.
A.are working
B.work
C.worked
D.will work
答案及解析: A
If a computer crashes, you will lose the file you ________ on unless you save it regularly.
A.are working
B.work
C.worked
D.will work
答案及解析: A