问题
选择题
Your pen is ____the 
____.[ ]
A. on; copybook
B. in; English book
C. in, English copybook
答案
C
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Your pen is ____the ____.[ ]
A. on; copybook
B. in; English book
C. in, English copybook
C
。A的合成路线如下图，其中B～H分别代表一种有机物。