矜持只是你一种掩饰
[jīn chí zhĭ shì nĭ yī zhŏng yăn shì]
'Reserve is just your disguise' suggests self-control and formality can be a person’s facade, possibly hiding something more authentic underneath. The user implies they are aware there’s a contrast between how they outwardly present themselves (quiet and composed) and their real personality.