2016卫生职称英语备考语法：方位介词across,through,over,past的用法辨析

介词across着重于“从一头或一边到另一头或另一边”，强调从表面穿过。

如：She went across the street to make some purchases.

A.介词through着重于“穿越”，强调从一定的空间内穿过。

如：The sunlight was coming in through the window.

B.介词over多表示从“上方越过”，如：He failed to go over the mountain; he had to go round it.

C.介词past表示从“面前经过”，如：Someone has just gone past the window.