25. It is believed that those who attend lessons _____ great concentration are more likely to be top ones.
A. on B. in C. with D. over
26. There are many spelling mistakes in this exercise book, so it is _____ but satisfactory.
A. anything B. nothing C. everything D. something
27. Retirement is obviously a very complex adjustment period and _____ you start planning for it, the better.
A. earlier B. earliest C. the earliest D. the earlier
