"put your books on top of the desk"
"only the top side of the box was painted"
upper side的用法和样例:
例句
"You are the big drop of dew under the lotus leaf, I am the smaller one on its upper side, " said the dewdrop to the lake. 露珠对湖水说道; "你是在荷叶下面的大露珠,我是在荷叶上面的较小的露珠"