between you and me

between you and me
10. between you and me or between ourselves 你我之间(的秘密)；只限于你我之间；我俩私下说说
11. in between sth
(indicating location) 位于(两者)之间
(indicating time span) 在(两个时间点)之间
See: between

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between you and me
adv. 只限于咱俩之间