买一送一

buy one, get one free / two for the price of one

to buy / to purchase

one / single / a (article) / as soon as / entire; whole; all; throughout / "one" radical in Chinese characters (Kangxi radical 1) / also pr. [yao1] for greater clarity when spelling out numbers digit by digit

to deliver / to carry / to give (as a present) / to present (with) / to see off / to send