十一、介词(preposition) Prepositions are a class of structural words that indicate various semantic relations between words or expressions.Prepositions are usually divided into the following three types: 1)简单介词(Simple Prepositions) about,across,after,against,among,around,at, before,behind,below,beside,besides,between beyond,but,by,down,during,except,for,from, in,like,of,off,on,over,near,past,round,since, through,till,to,towards,under,until,up,with,per, via;1 十一、介词（preposition) ◼ Prepositions are a class of structural words that indicate various semantic relations between words or expressions. Prepositions are usually divided into the following three types: 1)简单介词(Simple Prepositions) ◼ about, across, after, against, among, around, at, before, behind, below, beside, besides, between, beyond, but, by, down, during, except, for, from, in, like, of, off, on, over, near, past, round, since, through, till, to, towards, under, until, up, with, per, via;