---Please come here again.
-----I will surely ____ you when I come to your city someday.
A. drop in at B.drop in C.drop on D. drop in on
---Please come here again.
-----I will surely ____ you when I come to your city someday.
A. drop in at B.drop in C.drop on D. drop in on
D
drop in on +人 意为：顺便走访某人； drop in at+地方 意思是：顺便走访某地方。