人见人用演狗见狗用舔
[rén jiàn rén yòng yăn gŏu jiàn gŏu yòng tiăn]
Translated literally, this means 'people act in front of people, dogs lick in front of dogs'. It can suggest two things depending on context: 1) everyone behaves according to social standards around their own kind. 2) People put on acts (performances) while dogs just act naturally or express affection via licking which symbolizes genuineness.