two is a company, three is a crowd
Definition:  a third person is usually a problem in a company of two
Usage:  Gert and Marikie invited me to their house; I decided not to go as two is a company, three is a crowd

SEPEDI
Translation:  bobebi bo a swanelana, boraro ke lešaba
Proverb: taba ke ya babedi, wa boraro ke mpheyane

XITSONGA
Translation:  vambirhi i khamphani, vanharhu i tshungu
Proverb: ta vambirhi i ta vambirhi, wa vunharhu i maonhamhaka

TSHIVENḒA
Translation:  vhavhili ndi khonani, vhararu ndi tshigwada
Proverb: ndi zwa vhavhili, wa vhuraru u ḓa na samba