Look at book on the desk . Is it useful one ?--Yes, it is . In the book there is muc

--- Look at book on the desk . Is it useful one ?
--Yes, it is . In the book there is much advice on how to learn math well.
A. a, the
B. the, a
C. the, an
D. a, an

A. a, the(答案→)B. the, aC. the, anD. a, an解析：句意：看看桌子上的那本书。它有用吗？是的，书里有很多关于学好数学的建议。句中有on the desk限定这本书，用定冠词the,useful有用的，辅音音素发音，用a,故选B

哦，回答的不错