across、through的区别词性不同：1、cross作动词时，意为“穿过，横渡”，作介词意为“十字，十字路口”。I swam across the Changjiang River 20 years ago.20年前我横渡了长江。Look left and right before you go across the street.过马路时要左右看。2、through为介词，在立体空间中的“穿过”。如: go through the forest“穿过森林”，go across the street“穿过大街”。through表示“贯通、直穿、透过、穿过”的意思，即是从一头(边)贯穿到另一头(边)。The river runs through our city.这条河流经我们市。He passed through the hall.他穿过大厅。through与across都表示“穿过”，但用法有区别:1.through强调从人群或物体中间穿过，该动作在三维空间进行。The sun goes through the window.阳光透过窗户。The stream runs through th forest.这条小溪穿过森林。2.across指在某一空间从一段到另一端或呈十字交叉穿过，该动作在物体表面进行。She went across the street to do some shopping.Can you swim across the river?