玩儿深沉 wan er shen chen
指故作含蓄老练或说话慢且带有思考状。pretend to be sophisticated; speak in a way so as to deliberately mystify others.
例:你不必在我面前玩深沉。
You needn't pretend to be sophisticated in front of me.
(Source:http://www.chineseneighbor.com )