Assuming you made a typo: "We remember the last summer" would be: „Pamiętamy ostatnie lato” (or „Pamiętamy zeszłe lato”). The first one is both literal and functional translation but little ambiguous. „Ostatni” can mean both the one that was before and the one that won't be followed by anything.
„Ostatni taniec” (the last dance) - is it the previous dance or we won't be dancing any more? With „zeszły” (only used with time) and „poprzedni” we have no such problems.