Russian Construction “мы с тобой”, “мы с вами”, “мы с ними”

Did you know that in the Russian language, instead of saying “you and I, we” (я с тобой, я с вами) we usually say мы с тобой. The same happens to “they and I” (мы с ними), “me and him (her)” (мы с ним (ней)). We also use it when we mean “somebody else and I”: мы с другом (my friend and me), мы с коллегами (my colleagues and me), etc. The same happens to the constructions with они. For example, они с другом, which can be translated as “he and his friend”, “she and her friend”, они с коллегами (he (she) and his (her) colleagues)). Basically, in this type of constructions, мы means “I”, and они means “he” or “she”.

For example,

Раньше мы с тобой много гуляли. We used to walk a lot before.

Мы с ним поссорились. We (me and him) argued.

Они с друзьями уехали. He and his friends left.