问题

You must concentrate more ______ your English study. [ ]
A: to
B: in
C: on
D:at
B: in
C: on
D:at
正确答案是:
同类题型
Einstein, the famous scientist, was born _____ March, 1897. [ ]
did you have dinner last night? —In a restaurant.
______ of the students in my class plan to go abroad for ______ study in the future.
Try to give its meaning when you meet a new word. Don’t _____ your dictionary all the time.
Some scientists believe that there will be more robots inyears.