Questions and exercises are given by the puter, which decides to move the students ahead, review an easier level, give more work on the same level.
A. either, or
B. both, and .
C. whether, or
D. not only, but also
网友回答
A. either, or
B. both, and .
C. whether, or
D. not only, but also
解析： whether….or…..表选择。问题的给出是为了决定是提高水平还是做同一水平的题。故选C。