简单介词（Simple Prepositions）
e.g. about, above, behind, besides, down, during, in, near, round, since, towards, with
复合介词（Compound Prepositions）
e.g. from among, from behind, from under, inside, outside, within, without, into, onto, out of, upon, throughout
短语介词（Phrasal Prepositions）
e.g. according to, apart from（除……之外）, as a result of, as for/to（至于，关于）,
