She is careful to ________ her place before she shuts a book so that she can easily find where she stops reading next time she continues.

A.rebuild

B.mark

C.date

D.take

答案及解析： B

解析：

导解：本句表示在看书时作“标记”以便下次接着往下看，动词用mark，其余几项均无此意．