To put on an act; to feign; to make a show of; to pretend in an affected manner.
他总是喜欢在大家面前铺眉蒙眼，装作一副老实巴交的样子，实则心计很深。
He always likes to put on an act in front of everyone, pretending to be honest and simple-minded, but in reality, he is very cunning.
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