别以为穿着婚纱你就是新娘
[bié yĭ wéi chuān zhe hūn shā nĭ jiù shì xīn niáng]
Literally 'Just because you wear a wedding dress doesn't make you a bride,' the user is expressing skepticism or criticism towards superficial appearances, especially in situations involving false pretenses or overemphasis on outer appearances over true character.